T.rai:Aa.^j:sE' 


HE  OS  HATE 


81J.IOATE3,  &C: 


E11C11TWAKG3UL 


Jitc 


A  PRACTICAL  TREATISE 

ON 

SOLUBLE  OR  WATER  GLASS, 

SILICATES  OF  SODA  AND  POTASH, 

FOR 

SILICIFYING    STONES,    MORTAR,  CONCRETE, 
AND  HYDRAULIC  LIME,  RENDERING  WOOD 
AND  TIMBER  FIRE  and  DRY  ROT  PROOF, 
&c.,  &c.,  &c. 

WITH 

HOMMtKDSor  RKCEIPTS  for  SOAP,  CKMEMS,  PAINTS  &  WHITEWASHES, 
R.  B.  SLEEPERS,  WOODEN  PAVEMENTS,  SHINGLES,  Ac. 

ItY 

DR.  LEWIS  FEUCHTWANGER, 
Chemist  and  Mineralogist. 



Concluded  with  Various  Essays  on  the  Origin  and  Functions  of  Carbonic 
Acid,  Limestones,  Alkalies  and  Silica  ;  and  a  Complete  Guide  for 
Manufacturing  Plain  and  Colored  Glass. 


•WITH    S  E  V  E  12. -A.  Hi    W  O  O  X)  C  TJ  T  S  . 


NEW  YORK. 
Published  by  L.  &  .1.  W.  Feuchtwanger,  55  Cedar  Street. 

1870. 


Entered  according-  to  act  of  Congress,  in  tlie  year  1870, 
By  Dr.  Lewis  Feuchtwanger, 

In  the  Clerk's  Office  of  the  District  Court  of  the  United  States  for 
the  Southern  District  of  New  York. 


ItOBBRT  Maloolm,  Pkintbk,  49  Cedar  Strbet,  N.  Y. 


P  R  E;  K      C  E  . 


 ,4-^  

The  object  of  this  Trcatisi'  o!i  Soluble  or  Water  (xlass  is 
to  give  some  inforinntior)  •  to  the  inaiiy  iri(juiries,  which  liave 
been  directed  to  the  Antlior  for  some  years  past,  m  what 
manner  and  purpose  this  valuable  j)reparation,  so  hij^hly 
recommended  by  the  various  scientitic  journals,  can  be 
usefully  employed.  There  is,  as  yet,  no  book  published, 
treating  on  all  its  applications,  with  the  exception  of  a 
pamphlet  in  French  l)y  Kuhlman  hi  1859,  containing 
mostly  memoirs  to  the  French  Academy  and  the  application 
of  the  water  glass  by  calico  printers  and  cotton  manufacturers. 
It  is  for  this  reason  that  the  Author  felt  the  necessity  of  com- 
piling, all  that  is  scattered,  about  the  various  uses  of  the  solu- 
ble glass,  in  all  the  journals  and  Patent-OfKce  reports.  Not  a 
day  passes  without  receiving  orders  for  samples,  either  in  dry 
liquid  or  jelly  state,  with  particular  requests  for  explicit  direc- 
tions ;  nor  does  a  day  pass  without  being  importuned  by 
strangers  and  curious  people,  all  desirous  for  information  hoM* 
the  soluble  glass  would  answer  for  many  purposes  in  domes- 


I 


iv. 


TREFACE. 


tic  economy.  The  soap-makev,  who  has  been  using  it  in 
Europe  and  this  country  for  a  number  of  years,  wants  to 
know  more  on  the  subject  of  producing  a  cheap  and  good 
soap.  For  slates,  for  a  good  and  cheap  whitewash, 
for  a  fire-proof  paint,  for  a  hoop-skirt  or  shirt-collar,  for  a 
mucilage,  a  fire  and  water  proof  cement,  and  for  many  hun- 
dred other  uses  the  inquiries  are  made  ;  and  thousands  of 
samples  have,  for  the  last  ten  years,  been  distributed  to  the 
inquisitive  and  speculative  applicants. 

It  is  generally  known  that  the  Author  was  the  first  to 
introduce  the  soluble  glass  in  the  United  States,  and  has 
devoted  much  time  in  experimenting  with  it ;  and  he  has 
succeeded,  after  many  fruitless  trials,  to  create  a  demand  in 
many  branches  of  industry.  From  the  extensive  list  of 
y)atents  issued  in  Europe  and  the  United  States,  he  has  col- 
lected all  information,  along  with  that  obtained  from  the 
scientific  and  practical  journals,  and  experimenters  will  find 
in  this  Treatise  the  various  uses  and  applications.  Kuhlman's 
Pamphlet,  the  Mining  and  Engineering  Journal,  the  Trans- 
actions of  the  American  Institute,  the  Manufacturer  and 
Builder,  Scientific  American,  the  Annual  of  Scientific  Dis- 
covery, have  all  furnished  material  for  this  Treatise. 

Many  inteiesting  topics,  such  as  the  origin  of  the  saltpetre 
and  nitrate  of  soda  and  the  manufacture  of  blanc  fix,  had  to 
be  related,  and  will,  no  doubt,  interest  the  general  reader. 

Particular  attention  has  been  bestowed  upon  the  formation 
of  hydraulic  cements  and  artificial  stone,  for  the  reason  thjit 
more  inquiries  and  experiments  are  performed  in  this  branch 
than  in  any  other  of  domestic  economy ;  the  natural  stones, 


PREFACE. 

such  as  the  brownstorie,  sandstone,  limestone  and  brick  build- 
ing, will,  sooner  or  later,  after  an  exposure  to  the  atmospheric 
elements  and  rain  and  frost,  become  decomposed;  cracks 
and  fissures  will  then  produce  the  deterioration,  while  coated 
with  the  soluble  glass,  and  mixing  the  mortar  with  the  same 
and  impregnating  the  bricks,  much  is  gained  for  their  pre- 
servation. 

The  editor  of  the  Scientific  American  states,  in  a  late 
article,  that  "it  is  somewhat  remarkable  that  long  before 
this  the  art  of  making  artificial  stone  has  not  been  brought  to 
perfection.  Yet,  if  we  may  judge  from  the  great  and  increas- 
ing variety  of  processes,  patented  and  otherwise,  which  now 
press  their  claims  upon  public  notice,  the  time  is  ripe  for  the 
introduction  of  any  process  which  can  demonstrate  practically 
its  capacity  to  fulfill  the  requirements  of  the  case."  He  states 
further :  "  We  have,  for  the  last  two  years,  availed  ourselves 
of  every  opportunity  aftbrded  us  to  examine  and  test  speci- 
mens of  artificial  stone,  and  have  met  with  many  kinds  which 
have  very  little  merit.  Some,  however,  are  really  good 
stones,  and,  as  such,  must,  in  our  opinion,  come  largely 
into  use." 

The  silicification  of  R.  R.  sleepers,  wooden  rails  and  blocks  for 
pavement  is  in  importance  next  to  the  preparation  of  artificial 
stone.  The  comparison  of  the  wooden  and  iron  rails  has 
also  been  clearly  stated  here,  and  the  future  will,  no  doubt 
bring  to  light  many  facts  here  stated  but  not  yet  put  to  prac- 
tice. The  advantages  of  the  wooden  block  pavement  over 
all  other  kinds  such  as  Macadamizing,  gravelling,  cinders, 
boulders  and  stone  blocks  are  numerous,  and  if  properly  laid 


vi. 


PREFACE. 


will  withstand  long  years  of  the  hardest  kind  of  travel,  and 
there  are  but  two  important  points  in  the  wooden  pavement 
to  be  observed,  which  are  a  firm  and  even  foundation 
and  the  good  silicification  of  the  foundation  planks  and 
blocks. 

The  reason  why  the  Author  lias  devoted  so  much  space, 
upon  hydraulic  limes,  mortars,  paints,  whitewashes  and  the 
preparation  for  guarding  timber  against  dry  rot  and  confla- 
gration is  solely  to  prove  and  make  it  plausible  that  the 
application  of  soluble  glass  possesses  great  advantages,  and 
may,  with  very  little  expense,  give  additional  safeguards. 

The  receipts  and  directions  for  preparing  an  innnense 
number  of  the  most  useful  vehicles,  cements  for  buildings 
and  sidewalks,  paints,  varnishes,  &c.,  cannot  but  be  very 
acceptable. 

At  the  close  of  the  treatise  the  author  added  several 
essays  which  refer  to  the  main  subject,  such  as  that  on  car- 
bon and  carbonic  acid,  in  order  to  explain  the  wonderful 
properties  of  the  latter,  the  eff"ect  the  same  has  in  the  appli- 
cation of  the  carbonic  acid  gas  to  hydraulic  lime,  and  to  the 
construction  of  buildings.  The  other,  on  limestone,  is  proved 
for  the  purpose  of  thr3wing  some  light,  in  a  philosophical 
point  of  view,  on  the  sources  and  functions  of  this  all  pervad- 
ing natural  substance. 

The  essay  on  the  alkalies  potash  and  soda  was  written 
merely  to  show  the  sources  from  where  they  are  derived. 

The  article  on  sand  or  silica  is  partially  taken  from  the 
transactions  of  the  polytechnical  branch  of  the  American 
Institute,  before  whom  the  author  delivered  a  lecture  on  this: 


PREFACE. 


vii. 


subject,  and  he  has  added  as  a  guide  for  the  glass  manufac- 
turer all  the  details  for  producing  plain  and  colored  glass, 
and  an  extract  of  an  article  on  the  green  sand  of  New  Jersey, 
by  Joseph  B.  Lyman,  on  account  of  the  peculiar  properties 
of  that  substance,  which  may  at  some  future  day  be  employed 
in  the  production  of  silicates.  The  manufacturers  of  glass 
will  find  this  treatise  a  useful  guide. 


CONTENTS  OF  THIS  TREATISE. 


Preface,  Pages  1  to  12 

Preparation  by  Fuchs,    14 

"             Doebcreiner,   15 

Application  at  the  Brooklyn  Navy  Yard,   19 

"         "         Houses  of  Parliament,   18 

Liebig's  Proposition  of  the  Infusorial  Karth,   90 

Silica  and  Quartz  Synonymous,   88 

Physical  Description  of  the  Whole  Family,   26 

The  Use  of  Allialies,  Salt  Cake,  Fluorspar  and  Arsenic,   40 

Manufacture  of  the  Various  Kinds  of  Soluble  Glass,   44 

Plate  of  the  Apparatus,     

Description  of  Siemen's  Apparatus,  and  Directions   48 

The  Circular  for  the  Uses  of  Soluble  Glass,   52 

Chloride  of  Calcium  Gives  the  Indurating  Action   54 

Ransome's  Ex[)crimcnts  with  Sili'  cous  Stone,   •'•5 

Author's  Artificial  Stone,   66 

Great  Improvement  by  Hydrofluoric  Acid,  f   57 

Silification  of  Chalk,   68 

Hydraulic  Limestone  and  Mortar,   60 

The  Different  Kinds  of  Lime,   64 

Portland  Cement,  Iloman  Cement,   65 

Plaster  Cement  and  Keene's  Cement,   66 

Hydraulic  Lime  from  the  Puzzuolanas,   67 

Premy  and  Vicate  Tlicoiies  of  Hydranlicity,   68 

Deville's  and  liallard's  Application  of  Matrmsia,   71 

Author's  Discourse  on  Cements  before  the  Polytechnic  Association,. .  78 

Hydraulic  Cement  from  Uondout,  N.  Y.,   75 

Kuhlman's  Patent  Lime  Cemont   78 

Bouilly's  French  Cement  from  Pebbles,   79 

Common  Mortar  and  Hydraulic  Cement,   80 

The  Prevention  of  Wall-Damp,   81 

Another  Mode  of  Application  to  Damp  Walls  and  Cellarb,   85 

Fleury's  liemaiks  on  the  Alkaline  Silicates,   87 

American  Limestone  as  Hydraulic  Mortar,   90 

The  Theoretical  Causes  of  the  Hardening  Process,   92 

German  Hydraulic  Cement,   94 

Ancient  Mortars,   97 

Solidifying  I'roperty  Depends  upon  Clay,   108 

Oertlej^'s  Silica  Stone,   Ill 


X.  CONTENTS. 

iSilicification  Process,   Page  lia 

Eemarkable  Reaction  of  Hardening  Porous  Bodies,   118 

Formation  of  Saltpeter  and  Nitrate  of  Soda  Explained,   126 

Silicification  of  Sandstone,  White  Lead,  Chrome,  &c.,   124 

Silicate  Painting  on  Stone,   126 

Stereochronaic  Painting,   12T 

Application  of  Hydrofluoric  Acid  as  a  Fluo-Silicated  Lime,   131 

Stereochrouiic  Painting  for  the  Easel,   137 

Pernaanent  White,  or  Artificial  Sulphate  Baryta,   188 

Preparation  of  Blanc  Fix,   189 

Silicification  of  Wood,   140 

The  Construction  of  the  Munich  Theater,   141 

Full  Directions  by  the  Author   143 

Letheby's  liemarks  on  Dead  Oil,   147 

Violittier's    "       "     Desication  of  Wood,   148 

Wooden  Roof  Shingles  and  Farm  Houses,   149 

Preservation  of  Wood  by  Immersion,   151 

Champty  and  Payen,   152 

Popular  Method  of  Guarding  against  Decay,   155 

Methods  Pursued  by  the  British  Navy,   156 

The  French  Method  of  Preservation,   157 

Wooden  Railway  and  Wood  Paving,   158 

Prosser''s  System  Explained,   162 

Timber  Rot  and  Seasoning,    163 

Resiuiferous  Timber  Most  Durable,   167 

Robbins'  Process  for  Preserving  Wood,   171 

His  Discovery  of  One  of  the  Lost  Arts  of  the  Egyptians  a  Fallacy,   172 

Patent  of  1865  Anticip'!ited  by  Moll  in  1835,   175 

Recommended  by  Dr.  Krieg  in  1858,  ,.  176 

The  Simplest  Application  for  Wooden  Roof  Shingles,   176 

Street  Pavements  Compared,   180 

Broadway  Pavement   do   200 

Fisk  Concrete  Pavement,    200 

Hicolson      201 

McGonegal           "    202 

Stowe                 "    203 

Brown  &  Miller    "    204 

Bobbin  s              "    204 

Stafford               "    204 

Seeley's  Concrete  "    205 

Wooden  versus  Stone  Pavement,   205 

Mode  of  Application  of  Wooden  Pavement,   206 

How  to  Apply  the  Soluble  Glass,   207 

How  Many  Square  Feet  of  Wall  Covering,   208 

What  Dilution,   209 

Preservation  of  Brick  Walls,   209 

Protection  of  All  Wooden  Utensils  against  Fire,  Dry  Rot  and  Leakage,  210 

Silica  Cement  for  Bottoms  of  Iron  Ships,   212 

Most  Adhesive  Insoluble  ("ement,   212 

Cheapest  and  Best  Whitewash  for  In  and  Out  Door  Work,  Fences,  Ac,  213 


CONTENTS.  xi. 

Aquarium  Oeraent,   Page  215: 

Water-Tank  Lining,   214 

Tall'8  System  of  Concrete   214 

Concrete  liridge  in  London,    it! 

Soap  Substitute  of  Soluble  Glass   219^ 

Okie  Substitute,   221 

Mucilage  the  Trade  Mark  of  Solution,   221 

Enamellinjf  of  Culinary  Vessels.   222 

Porcelain,  Glass  and  Metal  Cement,   ^22 

Milk  Cement   22:T 

Marble    22? 

Zinc       "    224 

Foundation  Wall  Cement   224 

Gypsum                 "    224 

Hard  Adbfsive        "   225 

Drain  Pipe  llesistintr  a  Pressure  of  600  lbs.  to  the  IlcIi   225 

8tove  Cracks  (!ement,   226 

Cistern   22ff 

The  Most  Refractf)ry  Ceiiieni,     227 

Beton  Coignet  Buildinfr,   22iS— 236 

Essays  Rclatintr  to  this  Treatise   286 

The  Latest  Tables  of  Klements   239 

On  Carbonic  Acid,   23()— 273 

On  Limestones   978 

Their  Origin,   278 

Their  Preponderance  in  the  Newer  P'ormations   274 

How  to  Estimate  the  Relations  of  Finite  Powers  of  Man  and  the  Attri- 
butes of  an  Infinite  Being,   276 

Limo  is  the  Medium  between  Organic  Beings  and  the  Inorganir 

Progress,   276 

Lime  is  the  Oxide  Calcium,  which  is  One  of  the  Nine  Klements  ci 

Constituents  of  Itocks,   ^77 

Lyell's  Opposition  to  the  General  Opinion   278 

The  Origin  either  from  Deposition  or  (-hemical  Precipitation   2T8 

Human  Skeletons  in  the  British  and  Paris  Museums   279 

The  Coral  Reefs  Constructed  by  Polypiferous  Zoophytes   280 

Their  Operations  Described  by  Capt.  Kotzebue,   281 

They  are  2,000  feet  Thick,  and  Required  190,000  years  for  their  Con- 
struction,   282 

The  Tropics  the  Hot-Bed  for  their  Formation   282 

The  Principal  Kinds  of  Coral  Rock   283 

The  Reef- Building  Coral,  as  Described  in  Hirsch's  New  Journal, 

The  Arts,   286 

The  Other  Organic  Materials  Forming  Limestone  Rocks,   28ff 

The  Uncrystallino  and  Crystalline  Limestone  Rocks,   290 

All  Other  Varieties  of  Limestone   291 

The  Hot  Springs  of  Arkansas,   292 

The  Travertin  Formations,   293 

The  Chalk  Formation,   297 

The  Cretaceous  Marl  of  New  Jersey,   299 


xii.  CONTENTS. 

The  Division  of  the  Cretaceous  Period.    Page  300 

Metamorphic  Kocks  Explained,  ; . . . .  801 

New  York  Island's  (xeolog-y,   3OI 

Eight  Rocks  Compose  the  Island,     301 

Dr.  Stevens'  Ideas  Regarding  the  Island,   3O8 

The  Prevalence  of  Limestones  on  the  Island,    303 

They  Form  the  Sedimentary  Material,   304 

The  Aqueous,  Volcanic,  Plutonic  and  Metamorphic  Division  of  Early 

Days   305 

The  Present  Division  in  Stratified,  Unstratified  and  Vein  Condition, . .  305 
The  Division  in  Ages,  such  as  Azoic,  Silurian,  Devonian,  Carboniferous, 

Reptilian,  Mammalian  Age,  and  that  of  Man,   306 

Another  Division  of  tlie  Geological  Time,  such  as  Azoic,  Pa'.Tozoic. 

Mesozoic,  Cenozoic,  and  Era  of  Mind,   307 

Lyell's  Division  of  the  Tertiary  Period,  as  Eocene,  Miocene  and  Plio- 
cene Periods,   308 

The  Wealden  Period  is  150,000  Years  Old,   30» 

The  Origin  of  the  Alkalies,  Potassium  and  Sodium,  and  Application 

in  the  Soluble  Glass,  &c.,  

The  Manufacture  of  Soda  Ash  Detailed,   314 

Silica,  or  Sand,  Fully  ExpUined,   316 

Description  of  the  Greensand  of  New  Jersey,   318 

The  Physical  and  Chemical  Cliaracters  of  Quartz,   324 

The  Many  Varieties  of  Quartz  Miueralogically  Described,   326 

History  of  Glass  Making   328 

Materials  of  Glass,   32» 

The  Various  Divisions  in  the  Kinds  of  Glass  in  the  London  Exhibition 

of  1851,   332 

The  Present  Classification  according  to  the  Constituents.   33S 

The  Composition  of  All  the  Varieties  of  Glass,   340 

The  Artificial  Gems,   341 

Ideas  on  the  Uses  of  Glass,   342 


SOLUBLE  GLASS, 


Alrio  caller]  water  glass,  liquid  quartz,  or  alkaline 
silicate,  consists  essentially  of  silex  and  one  or  two 
alkalies  heated*  to  fusion;  it  is,  therefore,  a  silicate, 
either  as  silicate  of  potassa,  silicate  of  soda,  or  a 
mixture  of  these  tw^o  alkalies,  a  silicate  of  potassa  and 
lime,  the  composition  of  Bohemian  glass,  or  a  silicate 
of  soda  and  lime,  like  the  English  crown  or  spread 
glass ;  and  if  there  is  oxide  of  lead  added  to  the  mix- 
ture of  silex  and  alkalies,  and  heated  to  continued 
fusion,  we  obtain  tliereby  a  flint  glass,  crystal  glass, 
or  strass,  a  paste  used  in  mock  jewelry. 

According  to  the  quantity  of  alkali  employed  in 
the  mixture,  the  product  is  made  soluble  or  insoluble. 
Bottle  and  window  glass,  for  instance,  which  con- 
tain less  alkali  and  some  oxide  of  iron  and  alumina 
(cl-ay),  are  more  dithcult  o^  fusion  than  other  kinds. 
The  soluble  glass  was  brought  to  practical  uses  by 
Professor  Fuchs,  of  Munich  in  Bavaria,  in  the  year 
1823,  by  igniting  strongly  in  a  refractory  furnace  or 
crucible  for  six  hours,  a  mixture  of  10  parts  of  pearl 
ashes,  15  parts  of  powdered  quartz,  or  line  sand,  and 
1  part  charcoal ;  tlie  mass  was  then  pulverized  and 


14 


SOLT^BLE  GLASS. 


added  in  small  portions  to  boiling  Avater,  until  the 
whole  is  dissolved  and  evaporated  to  a  specilic  gra- 
Yity  of  1.25,  at  which  point  the  carbonic  acid  of  the 
atmospheric  air  ceases  to  decomjiose  it.  The  highest 
concentration  of  the  liquid  is  42*'''  B;  when  still 
more  evaporated  it  is  obtained  in  a  solid  form,  re- 
sembling common  glass,  bnt  much  softer  and  more 
fusible.  The  liquid  standing  about  30^  B  is,  how- 
ever, the  most  proper  menstruum  for  application  to 
wood,  and  preventing  the  same  from  being  attacked 
or  kindled  bj  sparks  of  fire,  such  as  shingle  roofs, 
wooden  bridges  and  farm  houses.  Fuchs  prepared 
four  different  liquids,  and  employed  them  in  his  ex- 
periments : 

1.  The  simple  water  glass,  made  from  potassa. 

2.  The  soda  water  glass. 

3.  The  compound  of  both. 

4.  Another  liquid  which  he  used  for  fixing  paints 
on  a  coating  on  wood,  and  called  the  jelly  liquid. 

In  order  to  demonstrate  the  utility  of  the  water 
glass  in  making  wood  fireproof,  and  on  the  occasion 
of  the  burning  of  the  Royal  Theatre  at  Munich,  a 
wooden  shanty  was,  by  order  of  the  King,  erected, 
and  coated  inside  and  outside  with  a  weak  liquid  of 
silicate  of  potassa,  and  was  set  on  fire  on  each  corner  ; 
to  the  satisfaction  of  all  spectators  it  resisted  the  ele- 
ment nobly,  and  merely  charred  the  wooden  struc- 


SOLUBLE  GLASS.  15 

tiire,  without  pnuhicino-  a  lite  tire;  and  from  that 
time  tlie  water  glass  was  introduced  in  Germany. 
A  few  years  later  the  same  liquid  Avas  introduced  in 
the  mauufacturiuir  districts  of  England  as  a  substi- 
tute for  cow's  dung  by  the  cotton  mills,  and  was 
called  "  Dunging  Salt." 

The  author  having  studied  with  Doebereiner,  a 
professor  of  practical  chemistry  in  Jena,  who  was 
engaged  in  experiments  on  water  glass,  and  who 
proposed  an  alteration  in  its  composition,  such  as  the 
compcamd  of  potash  and  soda,  or  72  parts  of  carbon- 
ate of  potash,  854-  parts  of  carbonate  of  soda,  and  152 
parts  of  finely  pulverized  quartz,  which  proved  to  be 
a  better  substance,  conceived  the  idea  that  water 
glass  may  be  profitably  employed  in  this  country  for 
many  purposes.  In  company  with  ship  captains  and 
builders  he  offered  to  substitute  it  for  coppering  ves- 
sels, which  is  attended  with  that  expensive  metal 
the  copper  sheathing,  and  undertook  to  prepare  the 
ship's  timbers  in  such  a  manner  that  the  cells  of  the 
wood  could  be  filled  up  with  Silica,  or,  in  other 
words,  to  silicify  them,  and  produce  a  petrification 
of  the  organic  substance,  all  of  which  at  a  very  in- 
considerable expense,  in  the  Brooklyn  Navy  Yard, 
he  was  permitted  by  the  Ordnance  Department, 
under  the  direction  of  Commodore  Perry,  then  the 
Captain  of  the  Yard,  to  perform  the  experiments  witji 
the  spiles  on  the  various  docks,  which  were  destroyed 


SOLUBLE  GLASS. 


by  tlie  worms  {Teredo  navaUs)  so  fast  that  tliey  had 
to  be  replaced  every  three  years.  Also  the  cannon 
balls,  exposed  to  the  weather,  becoming  rusty  and 
w^orthless  in  a  few  years,  w^ere  varnished  with  his 
own  preparation,  and  the  addition  of  asphaltum,  and 
his  experiments  proved  highly  satisfactory,  as  in  both 
instances  of  applications  many  years  afterwards  indi- 
cated their  preservation. 

The  water  glass  was  neglet^ted  for  many  years  ex- 
cept by  the  military  authorities  in  Prussia,  and  we 
hear  that  the  soldiers  Avere  instructed  to  wash  their 
linen,  and  the  State  Prison  at  Si)andau  introduced  it 
for  washing  the  prisoners'  under  garments ;  and  it 
was  proved  so  economical  that  one  gallon  of  concen- 
trated liquid  was  sufficient  for  washing  1,000  pieces. 
Tiie  soap  manufacturers  began  to  use  it  in  England 
for  producing  a  cheap  soap.  Liebig  devoted,  in  the 
year  1850,  much  attention  to  the  subject,  and  at  the 
same  time  Kuhlmann  introduced  it  as  a  new  paint 
under  the  name  of  stereochromic  painting,  for  orna- 
menting the  interior  of  houses.  Pie  applied  the  fluid 
silicate  of  potassa,  obtained  by  dissolving  flints  in 
caustic  alkali,  with  the  aid  of  water  of  a  very  high 
temperature,  to  harden  chalk  and  porous  stone  ;  for 
he  observed  that  on  soaking  chalk  with  this  fluid 
silicate,  a  change  took  place :  part  of  the  chalk,  com- 
bining with  the  silicic  acid  of  the  silicate  of  potash, 
becoming  converted  into  silico  carbonate  of  lime, 


'SOLUBLE  GLASS 


17 


the  carbonic  acid,  thus  set  free,  combined  with 
the  potash,  in  time,  particularly  when  assisted  by 
lieat  and  dry  air,  the  coating  of  silico  carbonate 
was  found  to  pass  into  a  true  compact  deposit  of 
silica,  hard  enough  to  scratcli  glass.  The  solution 
of  silicate  of  potash  could  be  applied  either  with  a 
brush  or  a  syringe,  the  surface  being  first  cleaned  and 
scraped.  Three  .ap]>lication8  were  considered  suffi- 
cient. Although  successful  in  the  laboratory,  this 
method  failed  when  applied  to  buildings,  because  a 
dry  atmosphere  is  needed  during  tlie  whole  period  of 
hardening.  Not  long  after  this  suggestion  had  been 
made  by  Knhlman,  the  English  manufacturer,  Ean- 
some,  of  Ipswich,  engaged  in  the  manufacture  of 
silicate  of  soda,  following  up  the  above  experiments, 
attempted  to  fix  the  solution,  when  absorbed  with 
the  stone,  to  produce  a  double  decomposition  by 
absorbing  another  soluticm,  thus  leaving  an  insoluble 
deposit  within  the  sul)stance  of  the  absorbent  stones 
on  which  it  was  desired  to  act.  He  found  that,  l)y 
a  weak  acid  solution,  he  could  set  free  the  silica,  but 
in  that  state  the  deposited  mineral  had  no  cohesion. 
Following  up,  however,  the  application  of  the  fluid 
silicate  by  a  small  portion  of  chloride  of  calcium  (a 
waste  product  from  the  salines  and  acetic  acid  manu- 
facturers), it  resulted  that  the  chlorine,  parting  from 
the  calcium,  attacked  the  soda  of  the  silicate,  forming 
common  salt,  which  is  easily  dissolved  away,  while 


18 


SOLUBLE  GLASS. 


the  silica  acid,  set  free  and  combining  with  the  lime, 
formed  with  it  silicate  of  lime:  This  mineral  is 
nearl)^  insolnble,  very  hard,  and  adheres  with  great 
tenacity  to  foreign  snbstances,  as  is  illnstrated  in 
common  mortar.  Silicate  of  lime  thus  formed  resists 
carbonic  acid  and  dilute  sulphuric  acid,  and  is  little 
aliected  by  any  of  the  comrnon  alkalies  or  ammonia. 

The  etFect  of  this  treatment  on  stones  that  have 
not  already  been  inserted  into  buildings  has  been 
very  favorable,  and  they  appear  to  have  stood  without 
dcca}^  under  exposures  sufficient  to  produce  much 
injury  on  the  same  stone  unprotected  and  applied  on 
a  large  scale  to  buildings  that  have  already  shown 
symptoms  of  decay,  the  result  is  less  satisfactory  ; 
but  years  must  elapse  before  a  very  decided  opinion 
can  be  given  on  the  process.  After  some  time  we 
wdll  be  able  to  see  the  result  in  the  Houses  of  Parlia- 
ment and  Westmhister  Abbey,  where  the  magnesian 
limestone  has  been  treated  by  this  process. 

A  combination  of  Kuhlman's  process  with  a  tempo- 
rary wash  of  some  bituminous  substance  has  been 
tried  on  a  large  Fcale  in  the  Speaker's  (^ourt  of  the 
Houses  of  Parliament,  by  Szereling,  which  will  like- 
wise be  decided  after  some  time  upon  its  superiority. 

The  manufacture  of  the  water  glass,  or  soluble 
silicate,  or  soluble  glass,  has  only  been  known  since 
our  present  time,  although  the  various  kinds  of  glass, 
imitation  of  gems,  belongs  to  antiquity,  for  Pliny 


SOLUBLE  GLASS. 


19 


states  "  that  glass  was  first  discovered  by  accident  in 
Syria,  at  the  mouth  of  the  river  Belus,  by  certain 
mercliants  driven  thitlicr  by  the  fortune  of  the  sea, 
and  obliged  to  continue  there  and  drt^ss  their  victuals 
by  making  a  fire  on  the  ground,  where  there  being 
great  store  of  the  herb  hali^  that  plant  burning  to 
ashes,  its  salts,  mixed  and  incorporated  with  sand  or 
stones  fit  to  vitrify  or  make  glass."  The  word  kali 
was  explained  by  Boerhave  as  one  of  the  materials  of 
glass,  salt  and  sand  ;  the  salt  here  used  is  procured 
from  a  sort  of  ashes,  brought  from  the  Levant,  called 
polverine  or  rochetta,  which  ashes  are  those  of  a  sort 
of  water  plant  called  kali,  of  the  s])ecies  of  that  found 
in  some  parts  of  England,  called  frog-grass,  or  crab- 
grass,  cut  down  in  summer,  dried  in  the  sun,  and 
burnt  in  hea])S,  either  on  the  ground  or  on  iron 
grates,  the  ashes  falling  into  a  })it,  gj*ow  into  a  hard 
mass  or  stone,  fit  for  use."  This  material  evidently 
means  the  kelp,  Avhich  was  burnt  and  converted  into 
Barilla.  It  is  also  certain  that  Kunkel,  in  U)Y9, 
states  that  the  art  of  glass  was  already  brought  to  its 
highest  perfection,  and  expressed  that  Neri  in  his 
treatise,  "  l)e  Arte  Vitraria,"  has  communicated 
complete  knowledge  of  artificial  gems — much  is  said 
of  flexible  glass  not  rotting,  of  a  fusible  or  soluble 
glass,  of  which  Ya  i  llelmont,  the  chemist  of  the 
first  part  of  the  seventeenth  century,  knew  nothing. 
The  improvements  in  the  manufacture  of  the  soluble 


20 


SOLUBLE  GLASS. 


glass,  particularly  tliat  of  soda,  were  of  great  im- 
portance. He  had,  in  the  first  place,  discarded  the 
sand,  which  he  did  not  find  compact  enongh  for  pro- 
ducing a  good  paint,  and  substituted  the  flints,  found 
in  the  chalk  :  this  species  of  silex  he  exposes  under  a 
pressure  of  7-8  atmosplieric,  in  an  iron  cauldron,  to 
a  hot  soda  lye  standing  88®,  which  process  was  pa- 
tented by  the  brothers  Siemens,  in  the  year  1845,  with 
this  diU'erence,  that  they  produce  a  liquid  at  a  very 
high  temperature  corresponding  in  vapors  of  4-5 
atmospheres,  by  which  process  they  obtain  for  3-4 
time  the  quantity  of  silica  to  a  thin  liquid. 

Liebig  proposes  the  employment  of  the  infusorial 
earth,  which  dissolves  readily  the  caustic  soda  lye, 
whereby  he  obtains  240  parts  of  silica  jelly  from  120 
parts  infusorial  earth,  and  75  parts  soda  ash.  It  is 
well  known  that  the  infusorial  earth  is  pretty  ])ure 
silica  of  87  per  cent,  and  8  per  cent,  water.  The 
beds  of  Bilin,  in  Bohemia,  and  belonging  to  the  fresh 
water  Tertiary,  have  a  thickness  of  14  feet,  also  in 
Planitz,  in  Saxony.  Ehrenberg  estimates  that  about 
18,000  cubic  feet  of  the  siliceous  organisms  are  an 
nually  formed  in  the  harbor  of  Wismar,  in  the  Baltic 
Sea  ;  the  deposit  of  infusorial  earth  in  Richmond, Ya., 
contains  over  100  species,  and  forms  a  thick  stratum. 


SILEX,  OR  SILICA. 


This  substance  is  an  oxyde  of  silicinni,  and  bein^ 
tlie  main  body  of  onr  preparation  deseryes  a  full  and 
detailed  description. 

Silicium  is  the  metallic  basis  of  silica,  or  silex,  and 
is  equally  abundant  \yith  oxygen  as  a  constituent  of 
the  solid  surface  of  the  globe,  and  also  constituting  a 
large  portion  of  aerolites,  from  the  regions  of  space, 
and  this  metallic  base  was  discovered  by  Eerzelius,  in 
1S23,  and  is  obtained  artilicially  in  the  following 
manner: — Weil  dried  silico  Huoride  of  potassium,  10 
parts,  are  mixed  with  8  or  9  parts  potassium  in  an 
iron  or  glass  tube,  and  the  potassium  fused  and 
stirred  with  the  salt  by  an  iron  wire.    It  is  then 
heated  by  a  spirit  lamp,  when  it  suddenly  becomes 
ignited  from  the  reduction  of  silica  by  the  potassium 
forming  a  brown  mixture  of  lluoride  and  siliciuret  of 
potassiimi.    It  is  thrown  in  cold  water,  when  hydro- 
gen is  evolved,  the  potassium  of  the  silica  not  being 
oxydized   by  water   and  the   silicium  separating. 
AVhen  the  .effervescence  has  ceased,  the  solution  is 
poured  off,  fresh  cold  water  added  and  poured  off, 
until  it  ceases  to  be  alkaline,  when  boiling  water  is 

1* 


22 


SILEX,  OR  SILICA. 


used  to  wash  the  silicium  as  long  as  it  extracts  any- 
thing. 

Silicium  is  inflammable  in  the  air,  by  heat,  about 
one-third  burning  to  silica,  which  removed  by  fluo- 
hydric  acid,  leaves  a  dark,  chocolate,  brown  powder, 
heavier  than  oil  of  vitriol,  is  combustible  either  in 
the  air  or  oxygen,  or  even  when  gently  ignited  with 
saltpetre. 

Silica,  or  oxide  of  silicium,  is  synonymous  with 
silicic  acid,  silex  and  pure  sand,  or  quartz,  in  its 
various  forms  and  appearances,  and  constitutes  a 
very  large  proportion  of  the  solid  crust  of  the  globe, 
dnd  is  the  principal  constituent  of  all  simple  mine- 
rals, and  forms  a  greater  variety  of  salts  than  any 
other  acid.  It  is  easily  prepared  pure  from  pow- 
dered quartz,  sand,  Felspar,  or  other  silicious 
minerals,  by  fusing  them  with  four  times  their 
weight  of  a  mixture  of  carbonate  of  potassa  and 
soda,  or  by  either  carbonate  alone,  dissolving  when 
in  dilute  muriatic  acid,  filtering  and  evaporating  the 
solution  to  dryness  by  a  gentle  heat,  digesting  in 
muriatic  acid,  filtering  and  washing  with  hot  water. 

This  silica  has  two  modifications,  the  one  soluble 
in  water  and  acids,  the  other  insoluble.  The  soluble 
is  that  obtained  in  the  above  process  for  preparing 
silica,  and  is  always  formed  by  fusing  silicates  v>ith 
alkalies,  but  may  also  be  formed  by  boiling  fine  Silex 
with  strong  alkaline  solutions. 


SI  LEX,  OR  SILICA. 


23 


It  is  soluble  in  water  and  acids,  and  when  the  so- 
lutions are  concentrated  it  usually  separates  as  a 
jell  J  [gelatinous  silica],  and  when  evaporated  to 
dryness,  passes  into  the  insoluble  modification. 

Silica  is  a  white,  gritty  powder,  insoluble  in  water 
and  acids,  infusible  in  the  highest  heat  of  our  fur- 
naces, but  fusible  in  a  stream  of  oxygen  driven 
through  an  alcohol  flame.  It  fuses  in  this  case  to  a 
clear  glass,  which  may  be  drawn  out  into  flexible 
threads.  When  the  fused  bead  is  dropped  in  water, 
it  becomes  so  hard  as  to  indent  a  steel  pestle  and 
mortar.  It  is  the  feeblest  acid  at  common  tempera- 
tures, but  by  a  high  heat  can  expel  all  volatile  acids. 

Quartz  is  found  in  nature  crystallized  in  a  great 
variety  of  forms,  the  rhombohedral  prevailing,  and 
for  the  most  part  hemihedral  to  the  rhombohedron, 
or  tetrahedral  to  the  hexagonal  prism.  The  annexed 
two  figures  give  some  idea  of  its  occurrence  : 


The  cleavage  is  very  indistinct,  sometimes  eflected 
by  plunging  a  heated  crystal  in  cold  water.  The 


24 


SILEX,  OR  SILICA. 


crystals  are  either  very  short  or  very  much  elon- 
gated, sometimes  line  aciciilar  usually  implanted 
by  one  extremity  of  the  prism,  occasionally  twisted 
or  b'3nt.  The  prismatic  faces  commonly  striated 
horizontally,  and  thus  distinguishable,  in  distorted 
crystals  from  the  pyramid.  Crystals  often  grouped 
by  juxtaposition,  not  proper  twins,  frequently  in 
radiated  masses  with  a  surface  of  pyramids,  or 
in  druses  having  a  surface  of  pyramids  or  short 
crystals.  Herkimer  and  Ulster  Counties,  of  the 
State  of  ^^"ew  York,  produce  quartz  crystals  of  the 
most  complicated  forms,  which  occur  from  the  size 
of  a  pin's  head  to  that  of  a  foot.  Quarts  is  also 
found  massive,  from  the  coarse  or  fine  granular  to 
flint-like  or  crypto-crystalline  ;  sometimes  mamillary 
stalactitic,  and  in  connectionary  forms. 

Quartz  has  a  hardness — T,  and  a  specific  gravity  of 
2.65  ;  a  vitreous  lustre  sometimes  inclining  to  resin- 
ous ;  splendent  and  nearly  dull ;  is  colorless  when 
pure,  but  often  having  various  shades  of  yellow,  red, 
brown,  green,  blue  and  black.  The  streak  is  white 
of  pure  varieties  ;  of  impure  often  the  same  as  the 
colors,  but  much  paler.  Quartz  is  transparent  and 
opaque ;  its  fracture  is  perfect  conchoidal  and  sub- 
conchoidal,  is  tough,  brittle  and  friable.  The  polar- 
ization of  quartz  is  circular,  there  being  a  colored 
centre  instead  of  a  central  cross,  and  the  rings  of 
color  around  enlarging  as  the  analyzer  is  turned  to 


STLEX,   OR  SILICA. 


25 


the  right  in  right-liaiided  crystals,  or  left,  in  left- 
handed,  and  colored  spirals  are  seen  which  rotate  to 
the  right  or  left  when  the  incident  light  and  emerged 
light  are  polarized,  one  circnlarlv,  and  the  other 
plane. 

Pure  silica,  which  has  the  symbol  of  Si,  consists 
of  58-83  parts  oxygen,  and  46-67  silicon — 100.  It 
is  unaltered  if  brought  alone  before  the  blow-pipe, 
but  with  soda,  it  dissolves  with  eti'ervescence  ;  it  m 
unacted  upon  by  any  salt  of  phosphorus ;  it  is  only 
soluble  in  iluohydric  acid.  There  arc  two  varieties 
of  quartz  in  existence — 

I.  The  crystallized,  or  [)henocrystalline,  which  is 
vitreous  in  lustre. 

II.  The  fluid-like,  massive,  or  cryi)to-crystalline. 
The  tirst  division  includes  all  ordinary  vitreous 

quartz,  whether  having  crystalline  faces  or  not ; 
while  the  second  variety  has  been  acted  upon  some- 
what more  by  attrition  and  chemical  agents,  as  fluo- 
ric acid,  than  those  of  the  flrst. 

The  following  species  of  quartz  belong  to  the  phe- 
nocrystalline,  or  vitreous  varieties: 

1.  The  ordinary  crystallized  quartz,  rock  crystal, 
which  is  the  colorless  (piartz,  or  nearly  so,  whether  in 
distinct  crystals  or  not. 

a.  The  regular  crystals,  or  limpid  quartz. 

b.  The  right-handed  crystals. 

c.  Left-handed  crystals. 


26 


SILEX,  OR  SILICA. 


d.  Cavernous  crystals,  having  deep  cavities  par- 

allel to  the  faces,  occasioned  by  the  inter- 
ference of  impurities  during  their  forma- 
tion. 

e.  Cap  quartz,  made  up  of  separable  layers  or 

caps,  one  to  the  deposit  of  a  little  clayey 
material  at  intervals  in  tlie  progress  of  the 
crystal. 

f.  Drusy  quartz,  a  crust  of  small  or  minute 

quartz  crystals. 

g.  Kadiated  quartz,  often  separable  into  radia- 

ted parts,  having  pyramidal  terminations. 
A.  Fibrous,  rarely  delicately  so,  from  Cape  of 
Good  Hope. 

2.  Asteriated  quartz,  star  quartz,  containing  within 
the  crystal  whitish  or  colored  radiations  along  the 
diametral  planes.  Part,  if  not  all,  asteriated  quartz 
is  asteriated  in  polarization,  as  already  remarked. 

3.  Amethystine  quartz,  amethyst,  clear  purple  or 
*  blueish- violet ;  the  color  is  supposed  to  be  due  to 

manganese,  the  shade  of  violet  is  usually  deepest  pa- 
rallel to  the  planes  R. 

4.  Rose,  rose  red  or  pink  quartz.  It  becomes  paler 
on  exposure,  common,  massive ;  and  then  usually 
much  cracked,  lustre  sometimes  a  little  greasy.  The 
action  is,  according  to  Fuchs,  due  to  titanic  acid ;  the 
general  impression  is,  however,  that  its  color  is  owing 
to  manganese. 


SILEX,   OK  SILICA. 


27 


5.  Yellow,  talse  topaz,  yellow  and  pellucid,  or 
nearly  so,  resembling  somewhat  yellow  topaz  ;  but 
very  ditferant  in  crystallization,  and  in  absence  ot 
cleavage. 

6.  Smoky  quartz ;  the  Cairngorm  stone.  It  is 
smoky  yellow  to  smoky  l)rowni,  and  often  transpa- 
rent, but  varying  to  brownish  black,  and  then  nearly 
opaque,  in  thick  crystals.  The  color  is  probably  due 
to  titanic  acids,  as  crystals  containing  rutile  are  usu- 
ally smoky.  It  is  called  Cairngorm,  from  the  local- 
ity in  Scotland. 

7.  Milky,  milk  white,  and  nearly  opaque ;  lustre 
often  greasy,  called  then  greasy  quartz. 

8.  Siderite,  or  sapphire  quartz,  of  indigo,  or  Ber- 
lin blue  colors.  A  variety  of  quartz  occurring  in  an 
impure  limestone  at  Golling,  in  Salzburg. 

9.  Sagenitic,  containing  within  acicular  crystals  ot 
other  minerals  :  these  acicular  crystals  may  be  rutile, 
or  black  Tourmaline,  or  Goethite,  stilbite,  asbestos, 
actinolite,  hornblende,  or  epidote. 

10.  Cat's  eye,  exhibiting  oj^alescence,  but  without 
prismatic  colors,  especially  when  cut  in  cabochon,  an 
etl'ect  due  to  fibres  of  asbestos. 

11.  Aventurine  quartz,  spangled  with  scales  ot 
mica  or  other  mineral. 

12.  Impure  quartz,  from  the  i)rcsence  of  distinct 
minerals  distributed  densely  through  the  mass,  such 
as  ferruginous,  either  red  or  yellow  oxide  of  iron, 


28 


SILEX,   OR  SILICA. 


cliloritie  from  elilorite,  aetinolitic,  micaceous,  arena- 
ceous owing  to  sand. 

Quartz  crystals  also  occur  penetrated  by  various 
minerals  as  topaz,  corundum,  clirysoberyl,  garnet, 
difl'erent  species  of  hornblende  and  Pyroxene  groups, 
kyanite,  zeolites,  calcite  and  other  carbonates  of  lu- 
tile,  htilbite,  hematite,  Goethite,  magnetite,  fluorite, 
gold,  silver,  anthracite,  &c.  As  quartz  has  been 
crystallized  through  the  aid  of  hot  waters  or  of 
steam,  in  all  ages  down  to  the  present,  and  is  the 
most  common  ingredient  of  rocks,  there  is  good  rea- 
son why  it  should  thus  be  found  the  enveloper  of 
other  crystals. 

13.  Quartz  containing  liquids  in  cavities.  These 
liquids  are  seen  to  move  with  the  change  of  position 
of  the  crystal,  provided  an  air  bubble  be  present  in 
the  cavity  ;  they  may  be  detected  also  by  the  refrac- 
tion of  light;  the  liquid  is  either  pure  water,  or  a 
mineral  solution,  or  petroleum-like  liquid. 

'II.  The  crypto-crystalline  varieties  of  quartz  are 
the  follow^ing : 

1.  Chalcedony;  it  has  the  lustre  nearly  of  wax, 
and  is  either  transparent  or  translucent  ;  the  color  is 
wdiite  grayish,  pale  brown  to  dark  brown,  black, 
tendon  color  common,  sometimes  delicate  blue  ;  also 
of  other  shades,  and  then  having  other  names;  it  is 
often  mammillary,  botryoidal,  stalactitic,  and  occur- 
ing  lining  or  tilling  cavities  in  rocks. 


SILEX,  OK  SILICA. 


29 


2.  Carnelian  ;  a  clear  red  chalcedony,  pale  to  deep 
ill  shade,  also  brownish  red  to  brown ;  the  latter 
called  sardonyx,  reddish  brown  by  transmitted  light. 

3.  Chrysoprase  ;  an  apple  green  chalcedony;  the 
color  is  due  to  the  presence  of  oxide  of  nickel. 

4.  Prase;  translucent  and  dull  leek  green;  taking 
its  name  from  the  Greek  npooaov^  a  leek. 

5.  Plasma  ;  a  rather  bright  green  to  leek  green, 
and  sometimes  nearly  emerald  green  color,  and  sub- 
translncent  or  feebly  translucent,  sometimes  dotted 
with  wliite. 

Heliotrope,  or  bloodstone,  is  the  same  stone  essen- 
tially, with  small  spots  of  red  jas])er,  looking  like 
drops  of  blood. 

The  jasper  of  the  ancients  was  a  semi-transparent 
or  translucent  stone,  and  included,  in  Plim^'s  time, 
all  bright  colored  chah-edony,  excepting  the  carne- 
lian ;  the  same  author  gives  special  prominence  to 
sky  blue  and  green,  and  mentions  also  a  shade  of 
purple,  a  rose  coloi",  the  color  of  the  morning  sky  in 
autumn  ;  sea  green,  sepcnthine  color  (yellow,  like 
sepentine),  smoke  color,  but  in  general  there  is  a 
tinge  of  blue,  whatever  the  shade. 

6.  Agate ;  a  variegated  chalcedony ;  the  colors 
are  either  banded  or  in  clouds,  or  due  to  visible  im- 
purities. 

(Banded  agate),  where  the  bands  form  delicate 
parallel  lines  of  white,  tendonlike,  waxlike,  })ale  and 


30 


8ILEX,  OR  SILICA. 


dark  brown  and  black  colors,  and  sometimes  bluish 
and  other  shades,  they  follow  waving  or  zigzag 
^courses,  and  are  occasionally  concentric  circular,  as 
in  the  eye  agate.  The  fine  translucent  agates  gradu- 
ated into  coarse  and  opaque  kinds.  The  bands  are 
the  edges  of  layers  of  deposition,  the  agate  having 
been  formed  by  a  deposit  of  silica,  from  solutions 
intermittently  supplied  in  irregular  cavities  in  rocks, 
and  deriving  their  concentric  waving  courses  from 
the  irregularities  of  the  walls  of*  the  cavity.  As  the 
cavity  cannot  contain  enough  of  the  solution  to  fill 
it  witli  silica,  an  open  hole  has  been  supposed  to  be 
retained  on  one  side  to  j)ermit  the  continued  supply, 
but  it  is  more  probable  that  it  passes  through  the 
outer  layers  by  osmosis,  the  denser  solution  outside 
thus  supplying  silica  as  fast  as  it  is  deposited  within. 
The  colors  are  due  to  traces  of  organic  matter,  or  of 
oxides  of  iron,  manganese,  or  titanium,  and  largely 
to  differences  in  rate  of  deposition.  The  layers  dif- 
fer in  porosity,  and  therefore  in  the  rate  at  which 
they  are  etched  by  fluoric  acid,  and  consequently 
the  etching  process  brings  out  the  different  layers, 
and  makes  engravings  that  will  print  exact  pictures 
of  the  agate.  Owing  also  to  the  unequal  porosity, 
agatei  may  be  varied  in  color  by  artificial  means. 

Irregularly  clouded  agate,  the  colors  various,  as 
in  banded  agate. 


SILEX,  OK  SILICA. 


31 


A  whitisli,  clouded  variety,  which  Pliny  has  de- 
scribed and  given  fully  the  characters. 

Y.  ( 'olored  agate,  due  to  visible  impurities ;  a 
moss  agate,  or  mocha  stone,  tilled  with  brown  moss- 
like or  (lentritic  Ibrms,  distributed  through  the  mass 
of  dentritic  agate,  containing  brown  or  black  den- 
tritic  markings.  These  two  have  been  fully  de- 
scribed by  Pliny  as  dentrachates. 

There  are  also  eight  agatized  woods,  wood  petriMed 
with  clouded  agate. 

7.  Onyx,  like  agate,  in  consisting  of  layers  of 
different  colors,  but  the  layers  are  in  even  planes, 
and  the  banding  therefore  straight,  and  hence  its  use 
for  cameos,  the  head  being  cut  in  color,  and  another 
serving  as  the  background. 

The  colors  of  the  best  are  perfectly  well  defined, 
and  white  and  black,  or  white,  brown  and  Idack 
alternate. 

S.  Sardonyx,  like  onyx  in  structure,  but  includes 
layers  of  carnelian,  along  with  others  of  white,  or 
whitish  and  brown,  and  sometimes  black  colors. 

9.  Agate  jasper.  An  agate,  consisting  of  jasper 
witli  veinings  and  cloudings  of  chalcedony. 

10.  Siliceous  sinter.  Irregularly  celluhu-  (piartz, 
formed  by  deposition  from  waters  containing  silica, 
or  soluble  silicates  in  solution. 

11.  Flint.  Somewhat  allied  to  chalcedony,  but 
more  opaque  and-  of  all  colors,  usually  gray,  smoky 


32 


silp:x,  or  silica. 


brown,  and  browninli  black.  Tlie  exterior  is  often 
whitish,  from  mixture  with  lime  or  chalk,  in  which 
it  is  imbedded.  Lnstre  barely  glistening,  subvitre- 
ons  ;  breaks  with  a  deeply  conchoidal  fracture  and  a 
sliarp  cutting  edge.  The  flint  of  the  chalk  formation 
consists  largely  of  the  remains  of  infusoria,  sponges, 
and  other  marine  productions.  This  mineral  con- 
tains, according  to  Fuchs,  ])artly  soluble  silica. 

12.  Ilornstone.  It  resembles  flint,  is  more  brittle, 
and  fracture  more  splintry.  Chert  is  a  term  often 
applied  to  hornstone,  and  to  any  impure  flinty  rock, 
including  the  jaspers. 

13.  Basanite,  lydian  stone,  or  touchstone.  A  vel- 
vet black  siliceous  stone  or  flinty  jasper,  used  on  ac- 
count of  its  hardness  and  black  color  for  trying  the 
purity  of  the  precious  metals.  The  color  left  on 
the  stone  after  rubbing  the  metal  across  it  indicates 
to  the  experienced  eye  the  amount  of  alloy.  It  is 
not  splintry,  like  the  hornstone  :  it  passes  into  a  com- 
pact, fissile,  siliceous  or  flinty  rock  of  grayisli  or  other 
colors,  called  siliceous  slate,  and  resembles  ordinary 
jasper,  of  various  shades. 

14.  Jasper.    An  impure  opaque  colored  quartz. 

a.  The  reducing  to  hematite,  or  sesquioxide  of 
iron. 

1).  The  yellow  or  brown,  colored  by  the 'hydrous 
sesquioxide  of  iron,  and  becoming  red  when 
so  lieated  as  to  drive  ofl'  the  water. 


SILEX,  OR  SILICA. 


33 


e.  The  dark  green  and  brownish  green. 

d.  Tlie  grajisli  blue. 

e.  Blackish  or  brown  black. 

f.  Striped  or  ribbon  jasper,  having  the  colors  in 

broad  stripes. 
g.  Egyptian  jasper  in  nodules,  which  are  zoned 
in  brown  and  yellow  colors. 
Porcelain  jasper  is  nothing  but  a  baked  clay,  and 
differs  from  true  jasper  ii]  being  fusible  on  the  edges 
before  the  blowpipe.    Ked  porphyry,  or  its  base,  re- 
sembles jasper,  but  is  also  fusible  on  the  edges,  being 
usually  an  impure  felspar. 

Quartz  is  also  found  in  the  following  forms: 

1.  Granular  quartz,  or  quartz  rock,  which  consists 
of  quartz  grains  very  firmly  comj)acted,  the  grains 
often  hardly  distinct. 

2.  Quartzose  sandstone. 

3.  Quartz-conglomerate.  A  rock  made  of  pebbles 
of  quartz  with  sand.  The  pebbles  are  sometimes 
jasper  or  chalcedony,  and  make  a  beautiful  stone 
when  polished. 

4.  Itaoolumite,  or  flexible  sandstone..  A  friable 
sand  rock,  consisting  mainly  of  quartz  sand,  but  con- 
taining a  little  talc,  and  possessing  a  degree  of  flex- 
ibility when  in  thin  laminae. 

5.  Buhrstone.  A  cellular  flinty  rock,  having  the 
nature  in  part  of  coarse  chalcedony. 

C.  Pseudomorplious  quarts.    Quartz  appears  also 


34 


SILEX,  OR  SILICA. 


under  the  forms  of  many  of  the  mineral  species, 
wLicli  it  lias  taken  through  either  the  alteration  or 
replacement  of  crystals  of  those  species.  The  most 
common  quartz,  pseudomorphs,  are  those  of  caleite, 
baryta,  flnorite  and  siderite.  Tabular  quartz,  Hay- 
torite,  Beckite,  Babel  quartz,  silicified  shells  and 
silicified  wood  are  found  pseudomorphized  by  other 
minerals,  either  of  carbonate  lime,  Datholite,  fluor- 
spar, shells  and  wood.  The  texture  of  the  wood, 
for  instance,  is  well  retained,  it  having  been  foinied 
by  the  deposit  of  silica,  from  its  solution  in  the 
cells  of  the  wood,  and  Anally  taking  the  place  of  the 
walls  of  the  cells  as  the  wood  itself  disappeared. 

Dissolved  quartz,  or  liquid  silica,  occurs  often  in 
heated  natural  waters,  as  those  of  the  Geysers  of  Ice- 
land, New  Zealand  and  California,  mostly  as  a  solu- 
ble alkaline  silicate.'*' 

Quartz  is  one  of  the  essential  constituents  of  gran- 
ite, syenite,  gneiss,  mica,  shist  and  many  related 
rocks.  As  the  principal  constituent  of  quartz  rock 
and  many  sandstones,  as  an  unessential  ingredient 
in  some  trachyte  porphyry,  &c. ;  as  the  veinstone  in 
various  rocks,  and  for  a  large  part  of  mineral  veins  ; 
as  a  foreign  mineral  in  the  cavities  of  trap,  basalt 
and  related  rocks,  some  limestones,  &c.,  making 
geodes  of  crystals  or  of  chalcedony,  agate,  carnelian, 
ifec,  as  imbedded  nodules  or  masses  in  various  lime- 
stones containing  the  flint  of  the  chalk  formation, 


81LEX,  OR  SILICA. 


35 


the  hornstone  of  other  limestones ;  these  iiodnles 
becoming  sometimes  layers  or  masses  of  jasper  oc- 
casionally in  limestone.  It  is  the  principal  material 
of  the  pebbles  of  gravel  beds  and  of  the  sands  of  the 
seashore  and  river  sandbeds. 

Independent  of  the  quartz  proper,  as  has  been 
just  described,  nature  produces  a  vast  many  mine- 
rals composed  either  solely  of  silica,  with  slight  va- 
riations in  their  degree  of  hardness  or  specific  gravity^ 
such  as  the  following  : 

The  opal,  which  is  sub-divided,  in 

1.  The  precious  opal^  exhibiting  a  play  of  delicate 
colors. 

2.  The  fine  opal^  of  hyacinth  red  to  honey-yellow 
colors. 

3.  The  girasol^  of  bluish  white  color,  with  reddish 
reflections  in  a  bright  light. 

4.  The  common  opal^  in  part  translucent,  and  milk- 
white  to  greenish,  yellowish,  bluish.  Kesin  opal,  wax 
or  honey  color,  with  resinous  lustre.  Olive  green 
opal ;  brick-red  opal  ;  hydrophane,  a  translucent 
opal,  whitish  or  light  colored,  adheres  to  the  tongue, 
and  becomes  more  translucent  or  transparent  in 
water,  wherefore  its  name.  An  orange,  yellow  opal, 
called  Forcherte,  it  is  colored  by  orpiment. 

5.  Gachelong.  Opaque  and  bluish  white,  porcelain 
white ;  often  adheres  to  the  tongue. 


36 


SILEX,  OR  SILICA. 


6.  Opal  agate.  Agatelike  in  structure,  but  con- 
sisting of  opal  of  different  shades  of  color. 

7.  Menilite.  In  concretionary  forms,  tuberose, 
reniform ;  opaque,  dull  gray  and  grayish  brown. 

8.  Jaspopal.  An  opal,  containing  some  yellow 
oxide  of  iron,  and  having  the  color  of  yellow  jasper. 

9.  Wood  opal.    Wood  petrified  by  opal. 

10.  Hyalite.  Clear  as  glass  and  colorless,  consti- 
tuting globular  concretions  and  crusts. 

11.  Florite^  or  siliceous  sinter;  also  called  pearl 
sinter,  from  Santa  Flora,  in  Italy,  and  other  vol- 
canic rocks,  formed  from  the  decomposition  of  the 
siliceous  minerals  of  volcanic  rocks,  or  from  the  sili- 
ceous w^aters  of  hot  springs. 

12.  Float  stone  ;  also  called  s^vimming  quartz  ;  is 
light,  concretionary  or  tuberose  masses,  white  or 
grayish,  sometimes  cavernous. 

13.  Tripolite.  Infusorial  earth  ;  formed  from  the 
siliceous  shells  of  diatomous  and  other  microscopic 
species,  occurring  in  deposits  often  miles  in  area 
either  uncompacted  or  moderately  hard. 

a.  Infusorial  earthy  or  earthy  tripolite,  is  a  very 
fine  grained  earth,  looking  often  like  an 
earthy  chalk  or  clay  ;  but  harsh  to  the  feel, 
and  scratching  glass,  when  rubbed  on  it. 

h.  Randanite  ;  a  kaolin-like  variety  from  France. 

c.  Tripoli  slate.  A  slaty  or  thin  laminated  va- 
riety ;  fragile,  often  mixed  with  clay,  mag- 
nesia and  oxide  of  iron. 


SILEX,  OR  SILICA. 


3r 


d.  Alumocalcite.  A  milk-wliite  material,  very 
light,  having  a  hardness  of  only  1  to  IJ,  and 
a  sp.  gr.  of  2.174,  and  probably  a  variety  of 
tripolite. 

This  mineral  is,  probably,  the  most  economical  and 
useful  material  for  the  manufacture  of  the  soluble 
glass. 

The  opal  family  is  likewise  a  quartz,  but  a  little 
softer  and  contains  some  water,  is  soluble  in  a  heated 
solution  of  potash,  while  quartz  does  not. 

In  England  and  France  the  flints  from  the  chalk 
are  mostly  employed  in  the  manufacture  of  soluble 
glass  ;  but  in  the  United  States  clear  sand,  from  the 
river-bed  of  New  Jersey  and  Mississippi  Rivers,  are 
solely  used  in  its  manufacture.  Sand  generally  con- 
sists of  particles  of  quartz,  but  there  is  also  a  granitic 
sand,  containing  particles  of  felspar  as  well  as 
quartz,  where  it  has  not  been  long  enough  exposed 
to  meteoric  agents  to  decompose  the  felspar.  Sand 
usually  consists  of  grains  more  or  less  rounded,  but 
sometimes  angular,  and  then  preferable  for  mor- 
tar. There  are  several  varieties  of  the  sandstone, 
such  as  micaceous^  argillaceous^  marly  and  flexible. 
Common  sand  is  mainly  comminuted  quartz.  Gravel 
is  a  mixture  of  sand  with  pebbles.  Yolcaiiic  sand  is 
sand  of  volcanic  origin  :  either  the  cinders  or  ashes  or 
comminuted  lava.  Alluvial  sand  is  the  earth  deposited 

by  running  streams,  especially  during  times  of  flood  ; 

2 


38 


SILEX,  OR  SILICA. 


it  constitutes  the  flats  on  either  side  of  the  stream, 
and  is  usually  in  thin  layers,  varying  in  fineness  or 
coarseness,  being  the  result  of  successive  depositions. 
In  order  to  use  the  sand  for  the  manufacture  of  solu- 
ble glass,  which  shall  equal  that  manufactured  from 
flint,  or  infusorial  or  siliceous  earth,  it  is  best  to  di- 
gest the  sand  witli  chlorohydric  acid,  which  is  capable 
of  dissolving  all  the  foreign  substances,  and  then  by 
frequent  washings  and  drying  in  the  sun,  produces  a 
pretty  pure  silica.  Iron,  clay,  lime,  which  are,  more 
or  less,  found  in  the  mud,  may  easily  be  detected  by 
the  various  chemical  tests,  such  as  by  ammonia,  the 
iron ;  by  oxalate  of  ammonia,  the  lime  ;  and  clay,  by 
carbonate  of  soda. 

If  the  pure  crystallized  quartz,  flint  or  hornstone 
should  be  used  for  the  manufacture,  the  same  must 
be  reduced  into  coarse  or  granular  condition,  which 
is  efl*ected  by  calcining  the  mineral,  and  when  red 
hot,  cold  water  is  thrown  over  it,  whereby  it  becomes 
disintegrated  and  falls  to  pieces,  and  it  is  then  ground 
in  mills  used  by  the  glass  manufacturers. 

Before  closing  the  chapter  of  silica,  it  must  be 
stated  that  nature  has  given  us  a  vast  variety  of  sili- 
cates :  that  the  alkaline  silicates  of  soda,  potash  and 
lime,  which  are  called  the  soluble  silicates,  are  spread 
over  the  globe  in  such  quantities,  like  oxygen  com- 
pounds with  the  addition  of  many  other  bases  in  na- 
ture, that  there  are  very  few  mineral  substances  known 


8ILEX,  OR  SILICA. 


39 


in  which  silica,  representing  the  acid,  is  not  combined 
with  the  various  elements  and  forming  silicates  which 
are  again  divided  in  anhydrous  and  hydrous  silicates, 
all  of  them  having  ternary  oxygen  compounds.  The 
anhydrous  silicates  are  again  sub-divided,  as  1.  Bi- 
silicates;  2.  Unisilicates ;  and  3.  Siih-silicaies ;  while 
the  hydrous  silicates  are  again  divided  in  various 
sections.  The  whole  crust  of  the  globe  consists  in 
silicates.  The  felspar  mica  is  a  pure  silicate.  We 
have  a  soda  felspar,  and  a  potash  felspar,  and  a 
lime  felspar,  while  the  mica  is  a  compound  of  silica 
combined  with  some  other  bases,  such  as  alumina, 
magnesia,  &c.  The  zeolites  form  a  large  class  of 
silicates,  which  resemble  the  felspar,  but  contain 
water,  and  are  less  hard  and  more  fusible,  such  as 
the  analcime,  cliabasite,  stilbite,  heulandite,  &c. 

In  the  manufacture  of  soluble  glass,  the  alkali 
is  in  importance  next  to  the  quartz  or  silica  such  as  the 
soda  and  potash,  both  of  which  are  employed  as  the 
carbonates  which  ought  to  be  pure. 

The  carbonate  of  potash,  which  is  the  pearlash, 
must  be  free  from  foreign  saline  substances.  The 
glass  manufacturers  prepare  that  material  by  wash- 
ing it  freely  with  water  and  evaporating  the  solution 
to  the  formation  of  a  precipitate  of  salt,  and  then 
the  water  is  run  off. 

The  Soda  employed  in  the  manufacture  is  the 
soda  ash  of  commerce,  and  is  never  pure  enough, 


40 


SILEX,  OR  SILICA. 


containing  water  and  other  salts,  which  ought  to  be 
removed  from  it  bj  dissolving,  crystallizing,  and  then 
calcination  of  the  crystals. 

Sulphate  of  soda^  or  Glauber  salt,  has  been  used 
by  some  manufacturers  in  place  of  soda  ash,  which 
ought  not  be  employed,  as  the  same  is  partly  con- 
verted into  sulphide  or  sulphuret  and  oxsulphite  of 
sodium,  which  is  detrimental. 

Fluorspar^  a  fluoride  of  calcium,  may  be  added  to 
the  mixture  of  sand  and  alkali,  as  it  produces  a  more 
fusible  silicate,  which  will  harden  soon  after  applica- 
tion by  the  affinity  for  this  alkali.  In  the  produc- 
tion of  hard  cements,  the  fluohydric  acid  is  of  great 
service,  for  it  assists  in  the  hardening  of  the  mortar, 
and  forming  a  good,  permanent  cement. 

WJdte  arsenic  in  powder  [arsenious  acid],  and 
nitrate  of  soda  ^  are  used  in  this  composition:  they 
produce  a  white  soluble  glass  ;  while,  without  any 
admixture,  the  product  is  green.  From  three  to  eight 
per  cent,  of  either  are  used. 


0 


THE  MANUFACTURE  OF  SOLUBLE  GLASS. 


1.   The  POTASH  SOLUBLE  GLASS. 

It  is  obtained  by  mixing  15  parts  powdered  quartz 
or  pure  sand  with  10  parts  purified  pearl  ashes,  and 
1  part  charcoal  in  a  Hessian  crucible,  and  exposing 
the  mixture  so  long  to  a  beat  until  the  mass  after  six 
hours  has  become  vitrified.  Charcoal  is  employed 
for  assisting,  by  its  decomposition,  the  production  of 
carbonic  acid,  as  also  some  sulphuric  acid  which  may 
have  been  produced.  It  is  at  present,  however, 
omitted,  and  if  manufactured  on  a  large  scale  the 
vitrification  is  done  in  a  reverboratory  furnace  capa- 
ble of  holding  from  1,200  to  1,500  pounds.  The  ashes 
and  sand  must  be  well  mixed  together  for  some  time 
and  the  furnace  must  be  very  hot  before  throwing 
the  mixture  in  it,  and  must  be  constantly  kept  up 
until  the  entire  mass  is  in  a  liquid  condition.  The 
tough  mass  is  then  raked  out  and  throwni  upon  a 
stone  hearth  and  left  to  cool.  The  glass  mass  so  ob- 
tained appears  to  be  hard'  and  blistery,  of  blackish 
gray  color,  and  if  the  ashes  were  not  quite  pure  it 
will  also  be  adulterated  with  foreign  salts.  By  pul- 
verizing and  exposing  it  to  the  air  it  will  absorb 


42 


MANUFACTURE  OF  SOLUBLE  GLASS. 


the  acidity,  and  by  degrees  the  foreign  salts  will, 
after  frequent  agitation  and  stirring,  be  completely 
separated,  particularly  after  pouring  over  the  mass 
some  cold  water,  which  dissolves  them,  but  not  the 
soluble  glass.  The  purified  mass  is  now  put  into  an 
iron  cauldron,  containing  five  times  the  quantity  of 
hot  water,  in  small  portions,  and  with  constant  agita- 
tion, and  replacing  occasionally  hot  water  for  that 
which  evaporated  during  the  boiling,  and  after  five  or 
six  hours  the  entire  mass  is  dissolved  ;  the  licpiid  is  re- 
moved and  left  to  settle  over  night,  in  order  to  be 
able  to  separate  any  undecomposed  silex.  The  next 
day  it  is  evaporated  still  more  until  it  has  assumed 
the  consistency  of  a  syrup,  and  standing  ^S'^'B,  and 
is  composed  of  28  per  cent,  potash,  62  per  cent, 
silica  and  12  per  cent,  water.  It  has  an  alkaline 
taste,  and  is  soluble  in  all  proportions  of  water,  and 
is  precipitated  by  alcohol,  and  if  an}^  salts  do  efier- 
vesce  they  may  be  wiped  off.  The  color  is  not  quite 
white,  but  assumes  a  greenish  or  yellowish  white 
color. 

II.   The  MANUFACTURE  OF  SODA  SOLUBLE  GLASS  *.  To 

45  parts  silica  or  white  river  sand  are  added  23  parts 
carbonate  of  soda  fully  calcined,  and  3  parts  char- 
coal, and  is  then  treated  in  the  same  manner  as  the 
other  glass.  The  proportions  of  the  mixture  are 
altered  by  the  different  manufacturers,  some  propose 
to  100  parts  silex,  60  parts  aBliydrous  glauber  salt 


MANUFACTURE  OF  SOLUBLF:  GLASS. 


43 


and  15  to  20  parts  charcoal.  By  the  addition  of 
some  copper  scales  to  the  mixture,  the  sulphur  will 
be  separated.  Another  method  is  proposed  by  dis- 
solving the  fine  silex  in  caustic  soda  lye.  Kuhlman 
employs  the  powdered  flint,  which  is  dissolved  in  an 
iron  cauldron  under  a  pressure  of  7  to  8  atmospheres. 
According  to  Liebig  the  infusorial  earth  is  recom- 
mended in  place  of  sand  on  account  of  being  readily 
soluble  in  caustic  lye,  and  lie  proposes  to  use  120 
parts  infusorial  earth  to  75  ])arta  caustic  soda,  from 
which  240  parts  silica  jelly  may  be  obtained.  His 
mode  is  to  calcine  the  earth  so  as  to  become  of  white 
Colors,  and  passing  it  through  sieves.  The  lye  he 
prepares  from  75  ounces  calcined  soda,  dissolved 
in  five  times  the  quantity  of  boiling  water,  and  then 
treated  by  56  ounces  of  dry  slacked  lime  ;  this  lye  is 
concentrated  by  boiling  down  to  48  deg.  B  ;  in  this 
boiling  lye  120  ounces  of  the  prepared  infusorial 
earth  are  added  by  degrees,  and  very  readily  dis- 
solved, leaving  scarcely  any  sediment.  It  has  then  to 
undergo  several  operations  for  making  it  suitable  for 
use,  sucli  as  treating  again  with  lime  water,  l)oiling 
it  and  separate  any  precipate  forming  thereby,  which 
by  continued  boiling  forms  into  balls,  and  whicii  can 
then  be  separated  from  the' liquid.  This  clear  li(|uid 
is  then  evaporated  to  consistency  of  syrup,  forms  a 
jelly  slightly  colored,  feels  dry  and  not  sticky,  and  is 
easily  soluble  in  boiling  water. 


44 


MANUFACTURE  OF  SOLUBLE  GLASS. 


The  difference  between  potash  and  soda  soluble 
glass  is  not  material ;  the  first  may  be  preferred  in 
white  washing  with  plaster  of  Paris,  while  the  soda 
glass  is  more  fluidly  divisible. 

It  may  be  observed  that  before  applying  either 
soluble  glass,  it  ought  to  be  exposed  to  the  air  for  ten 
to  twelve  days,  in  order  to  allow  an  effloresence  of 
any  excess  of  alkali,  which  might  act  injuriously. 
There  are,  however,  many  methods  proposed  to  ob- 
viate this  difficulty,  and  which  will  be  mentioned 
hereafter. 

III. — The  DOUBLE  SOLUBLE  GLASS. 

This  is  a  compound  of  potash  and  soda,  is  prepared 
from  100  parts  quartz,  28  parts  purified  pearl  ashes, 
22  parts  anhydrous  bicarbonate  of  soda,  6  parts  of 
charcoal,  which  are  spread  in  such  manner  as  already 
described.  If  the  mass  is  fully  evaporated  to  dry- 
ness forms  a  vitreous  solid  glass  which  cannot  be 
scratched  by  steel,  has  a  conchoidal  fracture,  of  sea- 
green  color,  translucent  and  even  transparent,  has  a 
specific  gravity  of  1.43. 

lY.  The  SOLUBLE  glass,  after  Kaulbach,  for  the 
use  of  sterro-chromic  painting. 

It  is  obtained  by  fusing  3  parts  of  pure  carbonate 
soda  and  2  parts  powdered  quartz,  from  which  a  con- 
centrated solution  is  prepared,  and  1  part  of  which 
is  then  added  to  4  parts  of  a  concentrated  and  fully 
saturated  solution  of  potash  glass  solution,  by  which 


MANUFACTURE  OF    SOLUBLE  GLASS. 


45; 


it  assumes  a  more  condensed  amount  of  silica  with 
the  alkalies ;  and  which  solution  has  been  found  to 
work  well  for  paint.  Siemen's  patent  for  the  manu- 
facture of  soluble  glass,  consists  in  the  production  of 
a  liquid  quartz  by  digesting  the  sand  or  quartz  in  a 
steam  boiler  tightly  closed  and  at  a  temperature  cor- 
responding to  4-5  atmospheres,  with  the  common 
caustic  alkalies,  which  are  hereby  capacitated  to  dis- 
solve from  three  to  four  times  the  weight  of  silica  to 
a  thin  liquid.  The  apparatus,  which  was  patented  in 
1845,  is  well  known  in  this  country  ;  as  some  per- 
sons, many  years  later,  obtained  a  patent  for  the 
same  apparatus  in  the  United  States,  which  on 
inspection  does  not  differ  from  that  of  Siemens 
Brothers. 

Description  of  Siemen's  Apparatus  for  dissolving 
silica  in  soda  lye,  under  a  pressure  of  five  atmos- 
pheres, or  sixty  pounds  to  the  square  inch. 


2* 


46 


MANUFACTURE  OF  SOLUBLE  GLASS. 


The  whole  apparatus  consists  of  the  boiler  A,  and 
the  dissolving  kettle  B. 

Fig.  I  represents  the  front  side,  and  2  the  horizon- 
tal. A  and  B  are  connected  by  the  pipe  a.  The 
kettle  B  is  constructed  of  two  strong  walls,  with  a 
space  1)  of  the  width  of  1-2  inches. 

The  steam  passes  through  the  pipe  a  into  the  space 
J.  In  order  to  reach  the  mner  kettle,  which  is  per- 
fectly tight,  the  wall  c  has  to  be  unscrewed.  Under 
the  middle  of  this  wall  the  box  d  is  now  attached^ 
which  encloses  the  iron  pipe  ^,  passing  through  the 
length  of  the  kettle.  Then  the  shovels,  or  agitators, 
yy,  are  now  applied  with  a  wheel  g  at  the  end  for 
effecting  the  revolutionary  movement*.  The  steam- 
cocks  K  as  seen  at  the  front  wall  <?,  for  indicating  the 
stage  of  the  water  in  the  interior  kettle  ;  the  cock  i 
serves  for  pumping  and  discharging  the  solution,  and 
the  cock  h  for  letting  off  the  water,  which  was  con- 
densed in  the  steam  chamber  C. 

The  outer  kettle  is  surrounded  with  ashes,  or  any 
other  non-conducting  substance. 

The  boiler  is  supplied  with  ventils  and  manometers, 
and  the  kettle  B  is  tested  to  stand  a  pressure  of  80- 
100  pounds  per  square  inch. 

The  kettle  is  now  filled  with  the  necessary  quantity 
of  silex,  after  the  front  wall  has  been  screwed  on  by 
means  of  the  cock  and  is  filled  up  with  the  caustic 
lye,  which  is  composed  of  100  lbs.  carbonate  of  soda 


APPARATUS  FOR  DISSOLVING  QUARTZ 

UNDER  PRE88URB  OF  FIVE  ATMOSPHERES. 


ma.^ufacti;re  of  soluble  glass. 


47 


to  20  gallons  water,  and  1  lb.  of  silex  for  each  quart 
of  water  ;  when  filled,  and  the  steam  having  assumed 
the  tension  of  60  lbs.  to  the  square  inch,  as  indicated 
by  the  safety  ventil,  the  cock  m  is  opened,  when  the 
steam  passes  to  the  other  kettle,  and  condenses  on 
the  cold  wall  of  the  inner  kettle  ;  here  the  tempera- 
ture is  raised,  and  assumes  soon  a  pressure  of  sixty 
pounds,  which  point  is  indicated  by  the  escape  of 
steam  from  the  safety  valve.  Fire  is  now  kept  up  for 
six  to  eight  hours  under  a  constant  escape  of  vapor. 

During  all  this  time  the  shovels  or  agitators  are 
kept  in  motion  by  the  workmen,  and  tlien  tlie  silex 
contained  in  the  kettle  will  have  dissolved  from  80- 
90  per  cent.,  and  is  drawn  off,  and  may  be  re-filled 
for  a  new  operation. 

The  apparatus  may  undergo  some  modification  as 
the  agitators  get  a  different  form,  etc.,  etc. 

The  silica  to  be  employed  is,  as  already  stated  to 
be,  the  common  sand,  which  is  at  first  calcined  and 
thrown  in  water ;  when  dry,  it  is  ground  as  fine  as 
flour. 

The  liquid  silica  when  discharged  from  the  kettle 
may  be  evaporated  to  dryness,  when  it  assumes  a 
compact  mass,  a  vitroous  and  conchoidal  fracture 
and  a  hardness,  so  as  to  give  sparks  on  steel,  without 
the  brittleness  of  flint. 

The  solution  as  it  is  obtained  from  the  kettle  may 
be  converted  into  a  white  fine  stone,  by  adding  fine 


48 


MANUFACTUKE  OF  SOLUBLE  GLASS. 


sand,  until  it  assumes  a  plastic  mass,  say  3-4  parts 
with  the  addition  of  a  little  chalk  or  lime  and  white 
clay  ;  hj  exposing  this  mass  when  formed  into  press- 
ed stones  or  objects  to  the  atmosphere  for  some  time, 
the  stone  is  now  in  the  best  condition. 

Instead  of  fine  sand,  fine  powdered  dry  silicate 
may  be  substituted,  and  a  better  stone  thereby  ob- 
tained. 

When  the  mass  is  dried,  it  must  undergo  the  pres- 
sure of  a  hydraulic  press. 

The  addition  of  chloride  of  calcium  and  chloride 
of  iron,  either  in  liquid  state  or  in  dry  powders,  is 
highly  recommended  for  promoting  the  hardening 
process. 

Siemens'  remarks  of  the  application  of  the  silex 
liquid,  that  the  sand  to  be  employed  must  be  first 
calcined  and  then  thrown  into  cold  water,  and  after- 
wards ground  into  fine  powder,  which,  when  mixed 
with  his  liquid,  becomes  compact,  insoluble  and 
white,  possessing  a  vitreous  and  conchoidal  fracture, 
and  a  hardness  so  as  to  give  sparks  by  steel. 

The  same  gentleman  also  recommends  for  the  pro- 
duction of  a  white  stone,  to  work  up  the  fine  silex 
with  so  much  liquid  soluble  glass  so  as  to  form  a 
plaster  mass,  say  from  3-4  parts  of  the  sand  may  be 
required,  similar  to  potter's  clay,  and  adding,  at  the 
same  time,  a  small  quantity  of  chalk  and  fine  clay, 
whereby  the  mass  becomes  more  uniform  and  com- 


MANUFACTURE  OF  SOLUBLE  GLASS. 


49 


pact.  Prepared  in  this  manner,  objects  moulded  or 
pressed  from  the  mass  must  be  exposed  to  the  air  for 
some  time. 

For  monuments,  millstones  and  other  building 
material,  he  uses  1  part  liquid  silica  to  2  parts  fine 
sand  and  12  parts  coarse  sand,  which  mass  formed 
into  the  desired  sizes  or  objects,  after  being  dried 
long  enough  in  the  air,  are  left  in  a  heated  room  of 
75^  for  several  days,  and  even  to  the  boiling  point  of 
water ;  they  become  so  hard,  after  a  lapse  of  four  to 
six  days,  that  they  never  crack  or  fall  to  pieces.  It 
is  also  recommended  to  expose  the  mass  to  the  pres- 
sure of  a  hydraulic  press  before  exposing  to  the  air. 
For  obtaining  a  cement — roofing  and  wall  body — it 
is  advisable  to  add  the  chloride  of  calcium  to  the 
mass,  and  thereby  the  excess  of  alkali  is  absorbed. 

The  mass  so  formed  may  be  steeped  in  a  solution 
of  chloride  of  calcium,  or  chloride  of  iron,  before 
exposing  to  the  atmosphere.  In  all  these  cases  the 
silica  ought  to  be  employed  very  concentrated,  even 
in  jelly  form. 

The  uses  of  the  soluble  glass  are  here  condensed  in 
a  short  sketch  intended  as  a  circular  to  those  desirous 
of  obtaining  some  information  : 


50 


MANUFACTURE  OF  SOLUBLE  GLASS. 


"  THE  USES  OF  ^SOLUBLE    GLASS  (lIQUID   SILEx),  SILICATE  OF 

soda,  silicate  of  potash,  silicate  of  soda  and  potash 
(combined.) 

"  Liquid  silica  is  now  employed  in  the  arts  for 
many  useful  purposes,  and  particularly  for  preserv- 
ing stone  buildings  from  decomposition  ;  for  prepar- 
ing an  artificial  stone,  and  thereby  reducing  the  price 
of  building,  and  making  a  composition  more  orna- 
mental. Its  introduction  for  architecture  is  but  of 
recent  date,  and  the  true  and  proper  method  of  appli- 
cation not  yet  on  an  infallible  base ;  but  the  subject 
is  of  so  vast  importance,  that  experiments  are  con- 
tinually going  on  for  making  a  perfect  stone  from 
its  original  ingredients. 

The  cause  of  gradual  decomposition  of  building 
stone  is  attributed  to  the  expansion  and  contraction 
of  water  absorbed,  as  well  as  to  the  chemical  action 
of  carbonic  acid  of  the .  atmosphere,  which  abstracts 
portions  of  the  gases  from  the  silicates,  and  liberat- 
ing thereby  silica.  Many  palaces  in  Europe,  churches 
and  other  public  buildings,  have  been  refinished  by 
the  silicate,  such  as  the  Louvre  and  Notre  Dame  Ca- 
thedral in  Paris,  the  Houses  of  Parliament  in  London, 
and  in  other  dities.  Still,  its  general  application  has 
met  with  many  failures.    It  was  found  that  rain 

*  In  the  year  1832  Dr.  F.  prepared  a  quantity  of  soluble  glass  for  the  U.  S.  Gov- 
ernment to  preserve  the  cannon,  guns  and  bomb  shells  from  rust  or  oxidation  at 
the  Navy  Yard  in  Brooklyn,  to  the  fullest  satisfaction  of  the  late  Commodore 
Perry. 


MANUFACTURE  OF  SOLUBLE  GLASS. 


51 


counteracted  the  effect  before  the  alkali  has  had  time 
to  take  up  a  sufficient  quantity  of  carbonic  acid  from 
the  atmosphere  and  to  liberate  the  insoluble  silicate, 
the  coating  will  produce  cracks,  and  a  gradual  disin- 
tegration of  the  surface  or  compound  is  caused  there- 
by. Numerous  remedies  were  suggested  to  counter- 
act this  evil — the  chloride  of  calcium,  oxychloride  of 
magnesium,  the  bittern  of  the  salines,  and  hydroflu- 
oric acid.  At  present  a  concrete  stone  of  consider- 
able hardness  and  durability  is  now  prepared  by 
means  of  greater  pressure  and  proper  manipulation, 
the  main  object  being  to  neutralize  and  extract  the 
alkali,  and  to  form  a  solid  chemical  compound  by  a 
second  application  of  a  weak  wash  of  chloride  of 
calcium  or  magnesium.  The  object  is  now  fully 
achieved. 

'  "  Another  important  application  of  the  soluble 
glass  is  to  render  wood  non-inflammable,  and  stop 
any  communication  of  the  fire,  and  at  the  same  time 
proof  against  water  and  damp.  The  wood,  timber, 
or  other  substances,  after  being  boiled  for  several 
hours  in  the  soluble  glass,  then  exposed  in  tanks, 
containing  solution  of  lime  water  and  solutions  of 
chlorMe  calcium,  are  hereby  petrified. 

"  Railroad  sleepers,  cross-ties,  house,  ship  and 
bridge  timber  will  also  be  silicified  by  this  process. 
Telegraph  poles  become  more  durable  and  better 
non-conductors  of  electricity.    The  lining  of  barrels 


52 


MANUFACTURE  OF  SOLUBLE  GLASS. 


for  oil  and  other  liquids,  the  coating  of  tanks,  tubs 
and  cisterns,  flour  barrels,  to  prevent  the  flour  get- 
ting musty,  is  very  easily  and  eflectually  done  by  the 
proper  and  judicious  use  of  the  liquid  silica. 

"  Soluble  glass  may  be  mixed  with  paper  pulp,  or 
<;heap  vegetable  and  animal  fibre,  and  serve  for  the 
manufacture  of  a  variety  of  useful  articles,  such  as 
boxes,  trunks,  soles  for  boots  and  shoes,  patterns, 
moulds  and  handles.  Invaluable  and  of  the  highest 
usefulness^  the  soluble  glass  can  be  employed  in  fire- 
j>r  oof  paints^  cements^  varnishes,  etc.,  for  which  pur- 
poses the  daily  demands  are  sufficient  proofs. 

The  dentists  make  use  of  the  silica  for  mending 
their  plaster  moulds,  or  in  case  of  an  accident  to  the 
cast  of  a  set  of  teeth.  Valuable  documents  are  made 
fireproof,  and  parchment  board,  slates* and  marbles 
are  cemented  together,  and  cracks  and  crevices  filled 
up. 

The  woolgrowers  apply  the  silicate  of  soda  and 
potash  to  the  greatest  advantage  for  cleansing  or  de- 
greasing  the  fleece  wool  and  make  it  soft. 

"  A  hard  and  ornamental  cement,  which  can  be 
moulded  like  plaster  of  Paris,  is  obtained  from  the 
mixture  of  silicate  of  soda  and  ground  dolomite  or 
magnesian  limestone,  which  may  be  used  both  natu- 
ral and  calcined  in  equal  quantities,  and  before  the 
mass  is  dry  the  bittern  (chloride  of  magnesium)  from 
the  salines  is  added,  which  will  harden  it  at  once.  A 


MANUFACTURE  OF  SOLUBLE  GLASS. 


53 


good  cellar  and  roofing  cement  is  made  bj  adding  to 
this  mass  tliree  parts  of  white  sand. 

"  The  silicate  is  also  used  for  penetrating  firebrick 
and  clay,  in  order  to  make  them  more  fireproof,  and 
ajso  used  for  cementing  the  walls.  For  producing  a 
durable  putty  in  iron  castings,  such  as  furnaces, 
heaters,  stoves,  etc.,  and  also  for  mending  air-holes. 
Boiler  makers  can  produce  a  very  durable  lining  by 
making  a  cement  of  silicate  with  asbestos  and  man- 
ganese finely  ground,  it  renders  boilers  and  other 
metallic  vessels  perfectly  fireproof,  and  the  best  fire 
and  anti-rust  paint  for  iron,  steel  and  brass.  There 
are  a  great  many  more  useful  applications  in  which 
the  silicate  may  be  used." 

The  alkaline  silicates,  as  have  bet^n  here  described, 
have  a  bright  future  for  their  application  :  the  genius 
of  the  nineteenth  century  cannot  fail  to  accomplish 
the  perfecting  the  work  begun  fifty  years  ago,  and  to 
this  moment  still  liable  to  faults.  Ere  long  we  will 
be  enabled  to  produce  an  artificial  stone  which  shall 
excel  nature ;  we  will  be  able  to  produce  a  perfect 
silicification  of  wood  and  other  organic  matter  ;  we 
will  challenge  the  atmosphere  and  other  chemical 
productions  to  do  their  best  for  forming  a  decomposi- 
tion of  those  materials  obtained  by  the  new  acquired 
skill  to  resist  tlieir  action.  The  labors  of  Fuch,  Lie- 
big,  Kuhlman,  Vicat,  Temy,  Guerin  and  llansome 


54  MANUFACTURE  OT  SOLUBLE  GLASS, 


have  fairly  begun  their  work,  and  in  ten  years  more 
the  ship  builder,  carpenter,  mason,  painter,  the  rail 
road  contractor  and  the  mechanic  in  general  will 
consider  this  valuable  substance  indispensable. 

Among  the  most  simple  processes  in  the  silicifica- 
tion  or  manufacture  of  artificial  stone  is  that  of  Ran- 
some,  which  consists  in  the  following  manner : 

The  sand  after  being  dried  is  worked  up  in  a  mill 
with  the  soluble  silicate,  prepared  from  caustic  soda 
and  flints,  the  latter  being  dissolved  by  the  former, 
and  evaporated  down  to  a  specific  gravity  of  1,700. 
The  plastic  mass  thus  produced  is  obedient  to  the  will 
of  the  moulder,  and  can  be  manipulated  into  any 
form,  from  a  cube  to  elaborate  screens,  from  a  grind- 
stone to  an  exceedingly  chisseled  fountain.  The 
mass  so  prepared  is  then  saturated  with  chloride  of 
calcium,  applied  simply  by  immersion  or  assisted  by 
the  action  of  an  air-pump  ;  in  either  process  the  so- 
lution being  gradually  heated  to  a  temperature  of 
212^  F. 

The  indurating  action  of  tlie  chloride  of  calcium 
is  promoted  in  closed  chambers  connected  with  a 
steam  boiler.  When  this  has  been  carried  on  for  a 
sutiScient  length  of  time,  by  opening  a  cock  the  solu- 
tion is  forced  by  steam  pressure  into  a  separate  cham- 
ber, leaving  the  stone  to  cool  gradually  in  partial 
vapor,  by  which  all  danger  of  cracking  is  avoided ; 
a  casualty  which  is  liable  to  happen  when  large 


MANUFACTURE  OF  SOLUBLE   GLASS.  55 

masses  are  exposed  to  rapid  extremes  of  temperature 
in  the  open  air.  In  order  to  remove  or  extract  the 
sohible  salts  of  calcium  and  sodium  from  the  body 
of  the  stone,  which  is  effected  in  the  same  closed 
chambers  by  the  admission  of  steam,  or  steam  and 
water  alternately,  which  as  it  condenses  and  becomes 
saturated  with  the  salts  referred  to,  is  returnt  d  into 
the  boiler,  where  the  steam  is  generated,  and  the 
chloride  of  calcium  is  again  made  available  for  future 
operations,  thus  obviating  the  serious  loss  incurred 
by  washing  the  stone  in  the  way  hitherto  adopted. 

Mr.  li.  was  led  to  his  last  experiments  from  the 
many  faults  which  he  discovered  in  manipulating  ; 
he  supposed,  at  first,  that  by  mixing  sand  and  frag- 
ments of  stone  with  the  fluid  silicate  into  a  kind  of 
paste  and  exposing  them  to  the  air,  they  would  be 
permanently  solid.  But  he  found  that  stones  they 
made  very  soon  became  disintegrated  in  any  moist 
atmosphere,  and  particularly  in  England,  and  could 
never  indurate.  To  remove  this  serious  objection,  he 
subjected  them  to  the  action  of  heat  in  a  kiln,  and  he 
found  then  that  at  a  bright  red  the  cementing  mate- 
rial or  silicate  parted  with  some  of  its  free  alkali, 
the  portion  thus  renewed  combining  with  some  of 
the  sand  to  produce  an  insoluble  glass,  unaffected 
by  exposure  to  any  of  the  acids  present  in  the  air 
and  not  cracking  by  exposure  to  frost  when  damp. 
This  artificial  stone  could  be  made  so  porous  as  to  be 


MANUFACTURE  OF  SOLUBLE  GLASS. 

well  adapted  for  filtering  slabs,  or  it  could  be  so 
•compacted  by  mechanical  pressure  before  burning  as 
to  yield  a  material  not  inferior  in  its  power  to  resist 
^itmosplieric  action  and  even  absorb tioii.  Paving 
slabs,  garden  vases,  balusters,  tombstones  and  various 
.a,rcliitectaral  features,  often  constructed  of  terra  cotta, 
were  produced  of  superior  quality  and  greater  dura- 
l)ility.  The  stone  thus  made,  however,  after  some 
exposure,  was  found  to  become  unsightly,  owing  to 
the  efflorescence  of  the  saline  matter. 

This  patent  siliceous  stone  was  also  found  too  ex- 
pensive to  come  into  general  use  on  a  large  scale, 
but  the  inventor  has,  at  last,  succeeded  in  reacliing 
to  a  satisfactory  result. 

The  author  has,  many  years  ago  in  the  course  of 
his  experiments,  succeeded  in  preparing  an  artificial 
«tone  in  the  following  manner : — Fluorspar,  finely 
^ground,  is  mixed  with  the  powdered  soluble  glass, 
2  parts  of  the  first  to  1  part  of  the  latter,  the  mixture 
made  into  a  thin  paste  by  the  concentrated  liquid 
soluble  glass,  and  then  as  much  finely  powdered  shell 
limestone,  or  magnesian  limestone  added  until  the 
mass  becomes  thick  enough  to  form  into  moulds  or 
blocks,  whichever  may  be  desired,  after  an  expo- 
sure of  three  to  four  days  to  the  atmosphere  are 
treated  by  a  weak  solution  of  chloride  of  calcium  (2 
pounds  dry  chloride  to  the  gallon  of  hot  water), 
this  liquid  will  soon  be  absorbed  by  the  stone ;  it 


MANUFACTURE  OF  SOLUBLE    GLASS.  5T 

is  then  exposed  again  to  the  atmosphere  for  a  week-; 
a  dilute  hydro-fluoric  acid  is  then  applied  with  a 
sponge,  and  again  exposed  to  the  atmosphere  ;  after 
a  lapse  of  a  week  the  stone  is  as  hard  as  a  natural 
stone,  and  not  liable  to  crack  or  to  disintegrate. 

This  composition  is  much  easier  prepared,  and  in- 
stead of  common  lime,  chalk  may  be  substituted,  and 
the  result  is  still  more  favorable.  Instead  of  the  en- 
tire quantity  of  lime,  coarse  sand  may  be  partially 
added,  and  after  the  stones  are  inoulded,  are  exposed 
to  hydraulic  pressure,  and  then  exposed  to  the  air^ 
previous  to  which  the  chloride  of  clalcium  has  to  be 
throw^n  over  it.  The  price  of  hydro-fluoric  acid,  as 
is  used  for  this  purpose,  costs  about  26  cents  per 
pound,  and  this  suftices  for  ten  square  feet.  It  must 
be,  however,  observed,  that  the  soluble  glass  used  in 
this  process  was  the  potash  silica  and  not  the  soda 
silicate,  as  he  found  by  his  experiments  to  be  indis- 
pensable, the  soda  silicate  does  not  produce  that  du- 
rability and  hardness  that  the  potash  silicate. 

Furthermore  it  may  be  remarked,  that  exposing 
the  stone  so  prepared  may  be  subjected  to  a  high 
temperature  or  not ;  it  may  be  left  to  the  operator  to 
decide  whether  it  will  improve  the  stone  by  this  ma- 
nipulation. 

For  the  sandstone  imitation,  when  1  part  liquid 
soluble  glass  is  to  be  mixed  with  2  parts  powdered 
soluble  glass,  and  15  parts  of  sand  is  added,  it  is  ne- 


58 


MANUFACTURE  OF  SOLUBLE  GLASS. 


cessary  to  expose  the  mass  to  great  pressure,  but 
requires  not  the  addition  of  chloride  of  calcium, 
while  exposure  to  great  heat  is  indispensable. 

An  artificial  stone  may  be  also  obtained  by  the  use 
of  the  alkaline  silicates  with  common  chalk,  which 
by  mixing  even  cold  with  the  liquid  silica,  is  at  once 
converted  into  silicate  of  lime  aid  carbonate  of  soda 
■or  potash  :  this  composition,  when  exposed  to  the  air, 
becomes  in  a  few  days  hard  enough  so  as  to  resemble 
a  hydraulic  lime,  to  adhere,  when  wetted  again,  like 
a  cement,  which  may  be  used  for  restoring  cracks 
and  crevices  in  marble  works  and  monuments. 

Tlie  silification  of  chalk  has  led  to  numerous  ex- 
periments, and  resulted  in  the  production  of  artificial 
stone,  in  the  formation  of  hydraulic  lime,  hydraulic 
mortar  and  the  various  cements.  The  first  successful 
result  of  the  treatment  of  chalk  with  the  silicate 
solution  has  shown  that  the  hardening  of  the  chalk 
extended  to  the  depth  of  four  inches,  which  not  alone 
was  produced  from  the  decomposition  of  the  silicate 
by  the  carbonate  of  lime  (chalk),  but  also  by  the  car- 
bonic acid  of  the  atmosphere.  If  two  balls  of  chalk 
of  equal  size  and  quality  are  silicified  at  the  same 
time,  and  one  of  them  is  exposed  to  the  atmosphere, 
the  other  kept  under  a  bell  gh  where  the  carbonic 
acid  of  the  atmosphere  is  withdrawn,  the  first  will 
acquire  more  hardness  than  the  other,  which  proves 
that  the  silification  has  assumed  a  hydrate  of  silico — 


MANUFACTURE  OF  SOLUBLE    GLASS.  59 

carbonate  of  lime — which  looses  by  degrees  its  water 
of  crystallization  and  a  contracting  precipitate  of  si- 
lica, which  contributes  mainly  to  the  hardening  of 
the  stone. 

A  hydraulic  lime  may  be  obtained  by  the  mix- 
ture of  a  fat  or  rich  limestone  combined  with  solu- 
ble glass  in  a  dry  state,  say  10  parts  silicate  to 
lOCTparts  of  air  lime,  both  fine  powder,  which  proves 
plainly  the  theory  of  the  part  which  the  silicates 
play  in  the  production  of  the  native  limestone,  the 
artificial  hydraulic  lime,  mortar,  cements,  and  the. 
application  of  all  silicates  for  the  purposes  of  build- 
ing, production  of  artificial  stones,  and  the  conver- 
sion of  organic  into  inorganic  materials,  as  we  shall 
show  hereafter. 


HYDRAULIC  LIMESTONE,  CEMENTS  AND 
PLASTERS. 

It  is  necessary  to  explain  the  main  material  -Hised 
in  building,  which  is  lime,  before  we  can  proceed 
farther  with  our  subject  of  silicification,  or  imitation 
of  the  same  substances  by  means  of  art,  latterly  ac- 
quired, and  which  bids  fair  to  excel  nature.  From 
one  of  Anted's  lectures  on  practical  geology,  the 
following  article  on  cements  and  plasters  gives  a 
good  idea  of  their  importance : 

The  earliest  architectural  constructions  to  fasten 
together  the  bricks  or  stones  of  which  buildings  are 
made  were  of  various  kinds  ;  the  most  common  and 
familiar  is  called  mortar.  It  is  obtained  by  first  cal- 
cm  ing  common  limestone  in  a  kiln,  and  converting 
it  into  qnick  lime,  by  depriving  it  of  its  carbonic  acid. 
After  calv  "aing,  the  resulting  quicklime  is  a  whitish 
or  grayish  pow^dery  and  cracked  substance,  which,  on 
the  application  of  water,  absorbs  a  certain  quantity 
with  the  evolutioiv  of  much  heat,  and  falls  into  a  fine 
powder.  This  powul-^r,  further  moistened,  made  into 
a  thin  paste  with  watei-,^nd  mixed  with  two  to  three 
times  its  own  weight  of  siv.arp  sand,  is  called  mortar. 


HYDRAULIC  LmESTONE,  CEMENTS,   ETC.  €)1 

Slaked  lime,  or  hydrate  of  lime,  as  moistened  quick- 
lime is  called,  absorbs  carbonic  acid  from  the  air,  and 
in  time  mortar  is  reconverted  into  limestone  ;  but 
the  operation  goes  on  under  peculiar  conditions,  and 
the  result  is  also  peculiar  ;  for  a  film  of  silicate  of 
lime  is  formed  round  each  grain  of  sand,  and  thus 
the  whole  mass  and  the  stones,  between  which  it  is 
placed,  become  in  time  more  compact  than  the  par- 
ticles of  limestone. 

"As,  however,  there  are  different  kinds  of  limestone, 
more  or  less  impure,  the  result  will  be  limes  of  very 
different  qualities  and  properties.  These  require  spe- 
cial treatment  to  obtain  from  them  the  best  results. 
The  purest  carbonate  of  lime,  such  as  marble,  or 
chalk,  make  what  is  called  a  rich  lime,  setting  firmly 
only  in  dry  air,  while  the  very  impure  carbonates,  in 
which  clay  is  largely  mixed  with  the  limestone,  re- 
sult in  the  production  of  hydraulic  limes,  which  set 
more  or  less  rapidly  in  moist  air  or  even  under  water. 
Some  of  the  impure  limestones  are  used  in  the  manu- 
facture of  cements  by  the  admixture  of  definite  pro- 
portions of  foreign  ingredients.  Some  '  .les  by  the 
admixture  of  certain  substances  [as  puzzuolana]  with 
the  rich  limes  instead  of  sand  hydraulic  limes  are 
produced.  There  are  few  subje  ts  connected  with 
the  application  of  geology  th- ^  are  more  important 
than  the  determination  of  t\e  material  that  should  be 

used  and  the  treatment  adopted  in  various  countries 

8 


62 


HYDRAULIC  LIMESTONE, 


in  the  manufacture  of  cements,  mortars  and  stuccoes. 

"  Commencing  with  nearly  pure  carbonates  of 
lime,  it  is  not  difficult  to  trace  the  changes  that  take 
place  in  their  conversion  into  cements  ;  a  layer  of 
such  mortar,  not  too  thick,  placed  between  bricks  or 
stone,  which  are  themselves  absorbent,  and  kept  in 
dry  air,  dries  gradually  and  holds  together  such  sub- 
stances with  extraordinary  tenacity.  But  this  is  a 
work  of  years,  and  sometimes  even  centuries  must 
run  out  before  the  extreme  of  hardness  is  attained  ! 
It  is  not  unusual  to  find  imperfectly  hardened  mor- 
tars in  very  old  constructions.  The  mortar  that  fast- 
ened together  the  bricks  in  the  old  Roman  walls  is 
now  almost  everywhere  so  far  hardened  that  a  frac- 
ture takes  place  in  the  brick  rather  than  th*^  .cment. 

"  Limestone  is  widely  distributed,  \  Irnost  every 
variety,  however  impure,  can  be  burnt  for  lime.  In 
the  manufacture  of  good  common  mortar  to  set  in 
the  air,  pure  limestones  and  those  of  fair  ordinary 
quality  are  available ;  but  in  using  them  attention 
must  be  given  to  their  composition  and  even  texture  ; 
thus  the  hardest  limestones  and  marbles  make  the 
fattest  lime,  other  things  being  the  same,  but  each 
variety  yields  a  lime  of  different  quality,  distinct  in 
color,  in  weight,  in  the  greediness  with  which  it  ab- 
sorbs water,  and  in  its  ultimate  hardness.  The 
method  of  calcination  also  varies,  but  the  general 
j-esult  is  that,  after  burning  the  limestone,  the  result- 


CEMENTS,  ETC. 


63 


ing  quicklime  is  lighter  than  tlie  original  stone,  and 
differs  from  it  essentially.  To  determine  the  nature 
of  lime,  and  its  peculiar  properties,  perfectly  fresh 
samples  should  be  placed  in  a  small  open  basket  and 
immersed  in  pure  water  for  five  or  six  seconds ;  re- 
moved from  the  water,  the  loose  unabsorbed  water 
must  be  allowed  to  run  off,  and  the  contents  of  the 
basket  emptied  into  a  stone  or  iron  mortar.  Accord- 
ing to  the  nature  of  the  limestone  the  lime  will  now 
exhibit  come  one  of  the  following  phenomena  : 

"  1.  It  will  hiss,  crackle,  swell,  give  off  much  va- 
por, and  fall  into  powder  instantly. 

'*  2.  It  will  remain  inert  for  seme  short  time,  not 
exceeding  five  or  six  minutes,  after  which  the  results 
stated  in  (1)  will  be  eiiergetically  declared. 

"  3.  It  will  remain  inert  for  more  than  five  mi- 
nutes, sometimes  extending  to  a  quarter  of  an  hour; 
it  then  gives  otf  vapors  to  a  moderate  extent,  and 
cracks  without  noise  and  without  much  evolution 
of  heat. 

4.  The  lime  will  crack  without  noise  and  with 
little  steam,  but  not  until  an  hour  has  elapsed. 

5.  The  lime  will  become  scarcely  warm  to  the 
touch,  will  not  fall  to  powder,  and  will  crack  to  a 
very  small  extent. 

"  In  each  case,  before  the  effervescence  (if  any 
takes  place)  has  quite  disappeared,  the  slaking 
should  be  completed  by  the  addition  of  water,  not 


HYDRAULIC  LIMESTONE, 


thrown  upon  the  lime,  but  by  the  side  of  it,  and  the 
result  should  be  frequently  stirred,  more  water  be 
added,  till  the  whole  is  brought  to  the  consistence  of 
a  thick  paste.  When  the  mass  has  cooled,  which  will 
not  take  place  for  two  or  three  hours,  the  whole  should 
be  beaten  up  again,  until  a  firm  but  tenaceous  paste 
is  produced,  resembling  clay  prepared  for  pottery 
manufacture.  Vessels  being  then  filled  with  this 
paste,  or  obtained  from  each  variety  of  limestone, 
the  day  and  hour  of  immersion  should  be  marked 
upon  them,  after  which  they  are  left  to  solidify. 

"We  thus  obtain  a  test  of  the  nature  of  the  mate 
rials  used,  which  may  belong  to  one  of  five  classes— 

(1.)  Kicb  Limes. 

(2.)  Poor  limes. 

(3.)  Moderately  hydraulic  limes. 

(4.)  Hydraulic  limes. 

(5.)  Eminently  hydraulic  limes. 
"  The  w^ord  hydraulic,  as  applied  to  lime,  means 
only,  that  it  possesses  the  property  of  setting,  or  be- 
coming solid,  in  moist  air  or  under  water. 

"  Eich  limes  are  obtained  from  the  purest  and 
hardest  limestones.  When  slaked,  they  increase  to 
double  their  volume  ;  if  employed  alone  they  remain 
unaltered  even  for  years,  and  they  are  soluble  in  pure 
water.  Limestones  that  contain  from  1-6  per  cent. 
43f  foreign  substances,  such  as  silica,  alumina,  magne- 
sia, (fee.,  yield  rich  limes  ;  but  such     contain  frx^m 


CEMENTS,  ETC. 


65- 


15  to  30  per  cent.,  are  poor  limes;  they  increase  in 
bulk  but  little  on  slaking,  do  not  set  under  water, 
and  are  soluble,  like  the  rich  limes,  except  that  they 
leave  a  residuum.  The  fossiliterous  limestones  make 
bad  mortar,  as  the  slaking  is  irregular;  limestones 
containing  much  silica,  swell  in  setting,  and  may 
dislocate  the  masonry  executed  with  them.  Where 
alumina  is  in  excess,  the  lime  is  apt  to  shrink  and. 
crack.  Where  carbonate  of  magnesia  is  combined 
with  carbonate  of  lime,  as  in  the  magnesian  lime- 
stones, the  original  bulk  is  retained.  For  ordinary 
purposes,  moderately  pure  limestones  with  a  mixture 
of  foreign  substances  is  a  moderately  pure  limestone. 
Hydraulic  limes  are  of  great  value  in  construction, 
and  are  extremely  interesting ;  and  are  either  ob- 
tained naturally  from  the  burning  of  certain  varie- 
ties of  calcareous  rock,  or  are  manufactured  artifici- 
ally by  mixing  limestones  with  the  requisite  foreign 
ingredients,  or  by  combining  quick  lime  with  foreign 
materials,  such  are  the  Roman  cement,  Portland  ce- 
ment, Parker's  and  Rosendale  cements.  The  Port- 
land cement  is  largely  manufactured  at  the  mouth  of 
the  Thames  from  a  mixed  river  mud,  while  Roman 
cement  is  formed  from  the  nodules  found  in  the  cliffs 
near  Harwich,  all  owing  their  quality  to  argillaceous 
admixture  and  limestone  containing  from  15  to  25 
per  cent,  of  a  silicate  of  alurania,  will  burn  into  a 
good  hydraulic  lime.   It  is  also  quite  certain  that  the 


66 


HYDRAULIC  LIMESTONE, 


oxide  of  iron  and  carbonate  of  magnesia  exercise  a 
great  influence  in  rendering  limes  more  hydraulic. 
All  materials  intended  for  the  manufacture  of  ce- 
ments require  to  be  burnt  carefully  and  ground  down 
to  a  fine  powder,  and  the  best  cement  is  the  lightest. 
When  these  cements  are  intended  for  the  production 
of  an  artificial  stone,  from  ten  to  twelve  times  the 
weight  of  broken  stones  and  pebbles  are  added,  and 
form  also  an  excellent  concrete.  A  stone  made  from 
these  cements,  just  described,  w^ill  bear  a  strain  vary- 
ing from  20-60  pounds  to  the  square  inch. 

The  plaster  cement  is  obtained  from  the  gypsum, 
or  sulphate  of  lime,  abundant  in  England,  France 
and  the  United  States,  is  treated  like  common  lime- 
Btone  for  a  cement.  The  calcining  of  gypsum  does 
not  involve  its  decomposition,  but  the  water  of  solid- 
ification being  driven  off  by  the  calcination,  leaves 
only  a  soft  white  powder  called  plaster  of  Paris  ; 
when  this  is  again  united  with  water,  the  latter  is 
absorbed,  and  the  mass  becomes,  first,  plastic,  and 
then  solid,  but  it  cannot  be  brought  back  to  its  origi- 
nal condition  as  a  crystalline  mineral,  but  it  is  con- 
verted into  various  substances  used  as  cement,  such 
as  Keene'^s  cement,  if  alum  is  added  to  the  fine  pow- 
dered plaster ;  parian  cement,  if  borax  is  used ; 
Martin's  cement,  if  pearl  ashes  are  employed ;  a 
stucco  is  a  very  useful  material  for  ornaments  in  in 
and  out-door  work,  is  nothing  else  but  a  plaster  of 


CEMENTS,  ETC.  6T 

Paris,  finely  ground,  and  a  weak  glue  added  before 
mixing  it  with  water. 

One  of  the  richest  kinds  of  hydraulic  lime  may 
be  obtained  from  volcanic  minerals  mixed  with 
limes,  such  material  is  the  Puzzuolana.  found  near 
Xaples,  as  well  as  other  substances  found  in  large 
quantities  in  the  neighborhood  of  extinct  volcanic 
districts,  as  in  France  and  on  the  Rhine;  and  which, 
according  to  its  chemical  analysis,  coiisists  of  44  per 
cent,  of  silica,  15  per  cent,  alumina,  87  }>er  cent, 
lime,  4  per  cent,  magnesia,  and  12  per  cent,  oxide  of 
iron  ;  combined  with  lime  instead  of  fand,  have  the 
property  of  rendering  even  the  richest  limes  hydrau- 
lic, and  fit  for  use  for  every  description  of  works  exe- 
cuted in  the  sea  or  in  fresh  water ;  they  have  been 
used  from  time  immemorial  with  great  success,  and 
may  be  mixed  either  with  fat  or  hydraulic  limes  and 
silicate  of  soda  to  form  a  plastic  mass  and  assist  in 
the  setting  of  the  lime. 

In  regard  to  hydraulic  cements,  Fremy  says  that 
the  setting  of  cements  is  due  to  two  dilferent  chemi- 
cal actions  :  1.  To  the  hydration  of  the  aluminates 
of  lime,  and  2.  To  puzzuolanic  action,  in  which  the 
hydrates  of  lime  combine  with  the  silicates  of  lime 
and  alumina  :  he  found  that  alumina  is  even  a  better 
flux  for  lime  than  silica,  and  he  suggests  that  the 
very  basic  compounds  of  these  two  substances,  those, 
for  instance,  containing  from  80  to  90  per  cent,  of 


68 


HYDRAULIC  LIMESTONE, 


lime,  may  be  useful  in  the  iron  furnace  for  absorbing 
sulpliur  and  phosphorus,  and  free  the  metal  from 
those  noxious  impurities  ;  and  he  finds  that  no  sub- 
stance is  capable  of  acting  as  a  puzzuolana  except 
the  simple  or  double  silicates  of  lime,  containing  only 
from  30-40  per.  cent,  silicate,  and  sufHciently  basic 
to  form  a  gelatinous  precipitate  with  acid  ;  and  he 
confirnts  Yicat's  theory,  that  the  cause  of  the  setting 
of  hydraulic  cements  was  owing  to  the  formation  of 
a  double  silicate  of  alumina  and  lime  absorbing  wa- 
ters, forming  hydrates  and  causing  the  setting  of  the 
materials. 

"  Theory  of  Hydraulicity. 

"  Fremy  has  lately  published  his  researches  on 
hydraulic  cements,  and  in  giving  the  theory  of  their 
hydraulicity,  he  rejects  the  commonly  received  opi- 
nion that  the  setting  of  hydraulic  cement  is  due  to 
the  hydration  of  the  silicate  of  lime  or  that  of  double 
silicate  of  alumina  and  lime.  These  salts  form  no 
combination  whatever.  He  attributes  the  setting  of 
hydraulic  lime  to  two  chemical  actions  :  1st.  To  the 
hydration  of  the  aluminate  of  lime  ;  2d.  To  the  re- 
action of  hydrate  of  lime  upon  the  silicate  of  lime, 
and  the  silicate  of  alumina  and  lime  which  exist  in 
all  cements,  and  in  this  case  act  as  puzzuolanas. 

"  The  calcination  of  the  argillaceous  limestone 
3)roduce3  good  hydraulic  cement  only  when  the  pro- 


CEMENTS,  ETC. 


69 


portions  of  clay  and  lime  are  such  that  they  form 
in  the  first  place,  an  aluminate  of  lime,  represented 
by  one  of  the  following  formulae  :  Al  O3  Ca  O — Al^ 
O3  2  Ca  O  ;— Al,  O3  3  Ca  O  ;  in  the  second  place  a 
very  simple  or  multiple  silicate  of  lime  which  gelati- 
nizes with  acids  and  approximates  to  the  following 
formulae  :— Si  O,  2  Ca  O— Si  O,  3  Ca  6  ;  and  thirdly, 
free  lime  which  may  act  upon  the  preceding  puzzuo- 
lanic  silicates. 

"  In  many  cases  the  chemical  compo?ition  of  an 
argillaceous  limestone  is  not  only  the  condition 
which  determines  the  quality  of  the  cement,  the 
reaction  of  the  lime  upon  the  clay  must  take  place  at 
the  highest  temperature.  Indeed,  this  excessive  heat 
produces  the  hydraulic  elements  of  the  cement  in  the 
basic  conditions  which  the  setting  in  the  water  re- 
quires, and  which,  by  melting  the  aluminate  of  lime, 
gives  it  all  its  activity. 

"  HYDRAULicrrY  OF  Magnesia  Hydrates. 

"  Since  the  publication  of  Fremy's  paper,  Deville 
has  read  a  note  before  the  Academy  of  Sciences,  '  On 
the  Ilydraulicity  of  Magnesia,'  in  which  he  alludes 
to  a  specimen  of  magnesia  prepared  by  the  calcina- 
tion of  the  chloride  sent  to  him,  seven  years  before, 
by  M.  Donny.  A  portion  of  it  was  left  under  the 
tap  of  his  laboratory,  constantly  exposed  to  running 
water.    In  time  it  took  a  remarkable  consistence, 

3* 


HYDRAULIC  LIMESTONE, 


became  liard  enough  to  scratch  marble,  and  was  clear 
as  alabaster.  After  six  years  exposure  to  the  air,  it 
has  not  perceptibly  changed,  and  its  analysis  gave 
the  following  results  :  Water  27.7  per  cent.,  carbonic 
acid  8.3,  alumina  and  oxide  of  iron  1.3,  magnesia 
57.1,  sand  5.6.    Total  100. 

Thus  the  substance  appeared  to  be  essentially  a 
crystallized  hydrate  of  magnesia,  like  brucite,  which 
does  not  absorb  carbonic  acid.  To  prove  that  it  was 
really  so,  M.  Devil] e  prepared  magnesia  by  calcining 
the  nitrate,  powdered  it,  made  it  into  a  plastic  mte, 
and  sealed  in  a  tube  with  some  boiled  distilled  water. 
After  some  weeks,  the  mass  became  as  hard  and  com- 
pact as  the  otlier,  and  also  crystalline  and  translucid. 
After  drying  in  the  air,  this  mass  was  found  to  con- 
sist of  30.7  per  cent,  w^ater,  and  69.3  per  cent,  mag- 
nesia, showing  it  to  be  a  simple  hydrate  of  magnesia. 
With  similar  hydrate,  cast  of  medals  were  taken, 
which,  on  being  placed  in  water,  assumed  the  appear- 
ance of  marble. 

"  M.  Balard's  magnesia,  prepared  by  calcining  the 
chloride,  obtained  by  treatment  of  sea  water,  when 
brought  to  a  red  heat  shows  astonishing  hydraulic 
qualities,  which  are  partially  destroyed  by  calcining 
at  a  white  heat..  A  mixture  of  chalk  or  marble  and 
magnesia,  in  equal  parts,  forms  a  plastic  mass,  which, 
placed  under  w^ater  for  some  time,  becomes  hydrated 
and  extremely  hard. 


CEMENTS,  ETC. 


71 


Deville  finds  that  dolomite  rich  in  magnesia^ 
when  calcined  below  a  red  heat,  powdered  and  made 
into  a  paste,  forms,  under  water,  a  stone  of  extraor- 
dinary hardness.  When  dolomite  is  heated  to  bright 
redness  and  all  the  chalk  is  converted  to  quick  lime, 
the  paste  formed  with  it  breaks  up  under  water.  All 
these  important  experiments  of  Deville,  show  that 
magnesia  is  the  binding  material  which,  on  becom- 
ing hjdrated,  holds  together  the  particles  of  chalk 
or  marble,  and  thus  forms  a  compact,  homogenous 
-  stone. 

"  Hydraulic  Cements. 

"  Hydraulic  cements  owe  their  property  of  setting 
to  some  compound  formed  by  the  calcination  of  infe- 
rior limestones  containing  clay  and  silica.  AVhat  the 
chauge  is  that  is  produced  by  the  calcination  has 
hitherto  not  been  sufficiently  well  understood  to  ena- 
ble the  manufacturers  of  cements  to  work  with  abso- 
lute certainty  of  producing  a  uniform  product.  M. 
Fremy  has  recently  been  studying  the  subject,  and 
has  communicated  his  observations  to  the  Institute 
of  France.  He  found  that  the  calcination  of  a  calca- 
reous clay  gives  rise  to  an  aluminate  of  lime  and  a 
silicate  of  lime,  with  some  free  caustic  lime. 

"  It  is  this  mixture  that  hardens  when  brought  in 
contact  with  water.  According  to  Fremy  the  setting 
of  the  cement  is  due  to  the  hydration  of  the  alumi- 


T2  HYDRAULIC  LIMESTONE, 

nate  of  lime  and  the  combination  of  silica  with  the 
quick  lime.  The  presence  of  four  compounds  is  ne- 
cessary to  a  good  result:  1,  silicate  of  lime;  2,  sili- 
cate of  alumina;  3,  aluminate  of  lime ;  4,  caustic 
lime.  Fremy  prepared  every  one  of  these  com- 
pounds, and  studied  them  separately  and  together. 
He  made  the  interesting  observation  that  alumina 
was  an  excellent  flux  for  lime,  and  combined  with  it 
quite  as  readily  as  silica. 

"  The  calcareous  clays,  or  poor  sorts  of  limestones^ 
which  are  capable  of  setting  under  water,  do  not 
acquire  that  property  until  they  have  been  exposed 
to  a  high  heat.  One  of  the  secrets  of  the  preparation 
of  Portland  cement  is  the  high  temperature  employed 
in  its  calcination.  The  lime  and  alumina  must  be 
fused  to  secure  the  property  of  hydration.  The  alu- 
minate of  lime  is  the  most  important  agent  in  hy- 
draulic cements. 

"  Hydraulic  limestones  will  not  yield  a  good 
cement  unless  the  proportion  of  clay  and  lime  be 
such  as  to  form  a  compound  of  alumina,  with  one, 
two  or  three  of  lime,  and  the  silica  and  lime  be  in 
the  proportion  to  yield  a  bibasic  or  tribasic  silicate  of 
lime,  which  will  gelatinize  with  acids,  and  there  must 
be  an  excess  of  lime  to  be  left  over  in  a  caustic  state. 
The  presence  of  magnesia,  manganese  or  iron,  is  not 
at  all  necessary,  although  the  latter  is  always  con- 
tained in  the  poorer  limestones. 


CEMENTS,  ETC. 


7S 


"  An  average  sample  of  Portland  cement  will 
yield,  upon  analysis,  in  one  hundred  parts :  Lime, 
fifty-five  ;  iron,  seven  ;  alumina,  eight ;  silica,  twenty- 
four  ;  potash  and  soda,  three  ;  sand,  two  ;  water,  one. 
The  essential  constituents  are  the  lime,  alumina  and 
silica." 

The  Author  delivered  a  discourse  on  cements  be- 
fore the  Polytechnic  Association,  2Gth  April,  1866, 
of  which  the  following  is  the  substance  : 

Cements. 

"  Tlie  subject  for  the  evening — cements — was  here 
taken  up,  when  Dr.  Lewis  Feuclitwanger  exhibited 
a  number  of  minerals  used  in  diil'erent  kinds  of  ce- 
ments, and  read  the  following  paper  : 

"  '  The  meaning  of  cement  is,  a  paste  used  for  unit- 
ins:  solid  surfaces  without  always  forming  a  combina- 
tion with  the  constituents  of  either  surface.  Many 
cements  contain  pulverulent  substances  which  are 
mingled  with  a  glutinous  or  very  adhesive  material 
and  do  not  combine  chemically ;  others  again  form 
chemical  combinations.  Furthermore,  many  sub- 
stances are  capable  of  assuming  a  liquid  or  semi- 
fluid form,  and  are  thus  applied  betw^een  the  surfaces 
of  bodies  which  are  firmly  united  when  the  fluid  has 
solidified. 

"  '  The  most  common  cements  are  mortar  and  hy- 
draulic cement.  We  have  also  lutes  and  fire  cements ; 


T4  HYDRAULIC  LIMESTONE, 

but  as  it  is  important  to  ascertain  the  best  mode  of 
obtaining  a  good  hydraulic  cement,  that  is,  a  cement 
which  hardens  under  water,  I  will  at  once  take  up 
this  branch  of  the  subject,  premising,  however,  that 
•common  mortar  is  simply  a  mixture  of  lime,  water 
and  sand,  the  best  proportions  being  one  cubic  foot 
of  fresh  burnt  lime,  weighing  about  thirty-five 
pounds,  and  three  and  one-half  cubic  feet  of  good 
river  saud,  not  round,  but  angular ;  these,  wdth  oue 
and  one-half  cubic  feet  of  water,  produce  about  three 
and  one-half  cubic  feet  of  good  mortar. 

"  '  Hydraulic  or  Roman  cement  is  composed  of  cer- 
tain proportions  of  lime,  sand,  clay  and  water  :  after 
it  has  been  applied  a  few  days,  and  placed  under 
water,  it  becomes  very  hard  and  like  stone.  We  now 
find  walls  and  piers  which  are  kuown  to  have  been 
built  more  than  a  hundred  years  ago,  and  have  been 
exposed  under  water,  and  have  remained  as  solid  as 
iron.  The  name  Koman  cement  is  derived  from  the 
district  of  Fuzzuoli,  near  Naples,  where  the  natural 
material,  the  tufas  and  puzzuolanas,  are  in  great 
abundance.  The  Pontine  marshes  around  Home  and 
the  volcanic  tufas  near  Naples  have  always  afforded 
a  natural  cement,  for  they  are  composed  of  silica, 
alumina  and  lime.  Besides  these  tufas,  many  marls, 
belonging  to  the  sedimentary  rocks,  are  used  as  hy- 
draulic cement.  The  cement  stones  allied  to  the 
oolitic  formation  and  found  in  argillaceous  strata 


CEMENTS,  ETC. 


alternating  with  limestone  beds,  and  of  very  curious 
nodular  and  lenicular  forms  and  concretions,  on  the 
English  and  French  coasts,  and  in  this  country  the 
septaria,  toadstones,  Indus  hclmontii  of  various  sizes 
and  consisting  of  siliceous  clay  and  lime  strata  inter- 
woven, yield  the  proper  material  for  hydraulic  ce- 
ment. All  these  marls  contain,  according  to  analysis, 
about  seventy  per  cent,  of  carbonate  of  lime,  twenty 
per  cent,  of  silica,  and  twenty  per  cent,  of  clay,  and 
the  lime  when  calcined  becomes  caustic,  and,  in  com- 
bination with  silica,  forms,  under  water,  a  chemical 
compound,  as  a  hydrated  silicate  of  lime  ;  and,  by 
the  presence  of  clay,  which  is  a  silicate  of  alumina, 
forms  double  silicates  of  greater  solidity.  Ca  O — 
CO —Si  O3--AI,  O3. 

"  '  The  Roman  or  hydraulic  cement  mostly  con- 
tains, also,  magnesia  and  iron,  whether  of  any  essen- 
tial benefit  or  not  has  not  been  fairly  tested.  It  is 
certain  that  neither  of  tliese  substances  exercise  a 
pernicious  influence,  for  the  reason  that  dolomite,  a 
mao-nesian  limestone  found  in  ffreat  abundance  in 
this  country,  offers  a  fine  material  when  calcined 
with  any  marls  so  abundant  along  our  coast.  It 
produces  an  excellent  hydraulic  cement. 

"  '  The  analysis  of  the  hydraulic  lime  from  Rondout, 
on  the  North  River,  gives  in  one  hundred  parts : 


Carbonic  acid   35 

Magnesia   12 

Alumina   10 


Lime   2") 

Silica   15 

Iron   2 


76 


HYDRAULIC  LIMESTONE, 


"  '  Sand  or  quartz,  which  by  itself  is  unfit  for  a 
mortar,  when  calcined  with  lime  becomes  very  suit- 
able for  a  hydraulic  cement  or  artificial  stone,  for  it 
forms  a  silicate  of  lime.  More  than  thirty  years  ago, 
I  entertained  the  idea  of  preserving  timber  by  the 
infiltration  of  silicate  of  lime  into  the  cells  of  planks, 
timber,  and  through  tlie  double  chemical  affinity  of 
silicate  of  soda  and  sulphate  of  lime.  The  experi- 
ments I  made  then,  in  the  Brooklyn  Navy  Yard,  with 
pier  piles  and  wooden  vats,  were  very  satisfactory. 

"  '  For  w^ater-proofing  cellars  and  buildings,  not 
alone  the  best  hydraulic,  but  other  cements  have  of 
late  years  been  introduced  in  this  city  ;  for  instance, 
the  asphalt  cement,  which  is  very  extensively  em- 
ployed in  tlie  foundation  of  buildings.  Having 
made,  myself,  many  experiments,  for  a  number  of 
years  past,  in  order  to  introduce  the  silica  cement, 
or  the  soluble  glass  in  combination  with  alkaline 
earths  as  a  base,  and  met  with  varied  success,  I  beg 
to  ofi'er  here  a  sample  of  a  cement  which  consists  of 
silicate  of  lime  combined  with  manganese  and  fluor- 
spar, or  fluoride  of  calcium,  which  becomes  very 
hard,  and  which,  I  think,  will,  after  some  improve- 
ment in  the  preparation,  be  found  highly  useful  in 
keeping  dry  walls  and  cellars.  I  have  mixed  equal 
quantities  of  manganese,  limestone,  fluorspar  and 
dry  soluble  glass,  and  make  the  whole  mass  plastic 
by  the  liquid  soluble  glass,  and  apply  it  while  soft ; 


CEMKNTS,   ETC.  7T 

after  the  lapse  of  a  few  hours  it  becomes  v^ery  hard. 

"  '  Fire  cements  are  lutes,  for  crevices  and  joints, 
which  are  intended  to  be  used  for  furnaces,  iron  pipes 
and  retorts  exposed  to  constant  red  and  white  heat,, 
or  for  joining  gas  and  water  pipes,  and  many  other 
substances,  may,  if  judiciously  applied,  prove  very 
acceptable.  1  beg  to  offer  a  few  which  I  consider 
useful : 

'  No.  1.  lro?i  Cement  or  Lute. — Brick  dust  and 
fire  clay  in  equal  parts,  borax,  red  lead  and  sal  am- 
moniac, one-tenth  of  the  other  ingredients  ;  cast  iron 
turnings.  The  whole  mixture  made  up  with  water 
so  as  to  knead  them  together,  and  spread  it  in  layers. 
It  is  suitable  for  crevices  or  joints  of  iron  pipes,  fur- 
nace doors,  man  holes  of  boilers,  etc. 

"  '  No.  2.  A  Steam-resisting  Cement. — Two  parts- 
litharge,  one  part  sand,  one  j)art  slacked  lime;  made 
plastic  with  hot  glue. 

"  '  No.  3.  An  Iron  Cement. — Manganese  twenty- 
four  parts,  red  lead  five  parts;  formed  into  a  paste 
with  linseed  oil. 

"  '  No.  4.  Cement  for  Fastening  Iron  and  Stone. 
— Calcined  plaster,  iron  filings  and  hot  glue. 

The  three  following  arc  good  cements  for  cisterns,, 
etc. : 

"  '  1st.  Ten  parts  of  plaster  of  Paris,  two  of 
Glauber  salts,  four  of  clay,  and  four  of  lime 

^  2d.  Twenty-two  parts  of  clay,  nine  of  iron 


HYDRAULIC  LIMESTONE, 


filings,  sixty-three  of  lime,  one  of  magnesia,  one  of 
peal  ash,  and  ten  of  charcoal. 

'  3d,  Thirty  parts  of  sand,  seventy  of  lime,  three 
of  litharge,  made  up  with  linseed  oil. 

^'  *  A  very  remarkable  cement,  for  almost  any  sub- 
stance, is  made  in  the  following  manner:  Either  glue 
•or  gelatine  is  swelled  up  in  water  and  then  immersed 
in  linseed  oil  and  heated.  It  dissolves  and  forms  a 
paste  of  great  tenacity,  which,  when  dry,  resists 
dampness  perfectly.  Two  pieces  of  wood  joined  by 
it  may  separate  anywhere  except  at  the  joint. 

"  '  The  china  or  diamond  CL^ment,  for  joining  glass 
or  china  ware,  consists  of  gum  mastic  and  ammonia 
dissolved  in  alcohol,  to  which  is  added  hot  glue. 
Spalding's  glue  is  the  old  Berzelius  paste,  that  is, 
glue  dissolved  in  acetic  acid.  The  Japanese  cement 
is  rice  flour  made  into  a  paste  and  dried. 

"  '  In  1841,  a  patent  for  a  lime  cement  was  obtained 
by  Kuhlman,  who  adds  an  alkali,  like  soda  or  potash, 
before  calcining  the  limestone  with  sand  and  clay,  so 
as  to  produce  a  soluble  silicate  with  the  ingredients 
of  hydraulic  cement. 

"  '  The  Portland  stone  or  cement,  so  extensively 
used  in  England,  and  exported  largely  from  there  to 
:all  parts  of  the  globe,  and  forming  the  base  of  many 
patent  cements,  such  as  Keese's  and  others,  is  nothing 
bat  powdered  oolite,  a  mineral  lime  deposit.  Hame- 
lin's  mastic  cement,  another  very  celebrated  cement. 


CEMENTS,  ETC. 


79 


is  prepared  from  sixty-two  parts  of  oolite,  thirty-five 
of  sand,  and  three  of  litharge. 

"  '  The  celebrated  French  cement  of  Bouilly  is 
said  to  be  prepared  from  the  Boulogne  pebbles,  called 
golets,  which  are  marly  nodules  of  all  sizes,  like  the 
septarias  and  marly  concretions  of  other  countries. 
A  number  of  years  ago,  I  prepared  a  good  hydraulic 
cement  from  one  part  of  the  poorest  limestone,  one 
of  clay,  and  three  of  sand.  I  also  prepared  a  terra 
cotta,  which  is  likewise  a  cement,  composed  of  clay 
and  sand,  slowly  dried  and  calcined. 

"  '  Common  Mortak. 

"  '  Limestone,  an  im])ure  carbonate  of  lime,  when 
exposed  to  a  red  heat,  loses  carbonic  acid  gas,  and  the 
oxide  of  calcium  or  lime  remains.  This  process  of 
burning  lime,  as  it  is  called,  is  accelerated  by  the 
presence  of  moisture  in  the  stone,  or  by  the  introduc- 
tion of  a  small  quantity  of  steam  into  the  lime  kiln. 
The  hydrate  of  lime  reacts  with  considerable  power 
on  siliceous  compounds,  but  the  action  only  takes 
place  at  the  surfaces,  and  unless  the  lime  is  used  in 
very  thin  layers,  between  smooth  stones,  it  still  re- 
tains, in  the  centre  o^*  the  layer,  its  own  soft  and  fria- 
ble condition. 

"  '  In  order  to  make  the  hydrate  of  lime  effective 
as  a  cement,  it  is  mixed  with  sand,  one  of  the  most 
abundant  of  natural  compounds,  now  regarded  as 


80 


nYDKATJLIC  LIMESTONE, 


consisting  of  two  atoms  of  oxygen  and  one  of  silicon. 
Equal  parts  of  fine  and  coarse  sand  are  said  to  be 
better  than  either  (Quality  used  separately  with  lime. 
Mortar  designed  for  exterior  or  surface  work  is  gene- 
rally made  with  fine  sand.  When  lime  is  compara- 
tively free  from  impurities  and  crumbles  to  a  fine 
powder  on  being  slaked,  it  is  called  fat  lime,  and  will 
require  about  six  times  its  own  weight  of  sand,  or,  if 
estimated  by  bulk,  one  cubic  foot  of  semi-fluid  lime 
and  water,  called  the  milk  of  lime,  will  require  about 
three  or  four  cubic  feet  of  sand.  This  mortar  is  very 
effective  as  a  cement  when  well  dried  or  set,  but  if  it 
is  placed  in  water  the  lime  is  gradually  dissolved  and 
the  mass  is  disintegrated. 

"  ^  Htdraulic  Cement. 

"  '  For  all  permanent  structures  under  water  it  is, 
therefore,  essential  to  use  a  material  called  hydraulic 
cement,  which  is  a  mixture  of  lime  with  other  oxides 
possessing  the  valuable  quality  of  hardening  until  it 
has  the  solidity  and  permanency  of  the  masses  of 
rock  bound  together  by  it.  The  varieties  of  lime- 
stone from  which  hydraulic  cement  is  made,  when 
burned,  yield  a  lime  that  is  very  slowly  slaked.  All 
that  is  required  is  to  add  w^ater  until  it  attains  the 
consistency  of  dough,  it  will  then  harden  and  become 
concrete.  These  hydraulic  limes  may  be  made  arti- 
ficially by  mixing  with  impure  slaked  lime  a  quantity 


CEMENTS,   ETC,  81 

of  burnt  clay  in  the  proper  proportions.  The  cele- 
brated Koman  cement  was  a  porous  volcanic  rock 
found  at  Puzzucli,  near  l^aples,  and  called  there  puz- 
zuolana.  It  consists  of  silicate  of  alumina,  soda  and 
lime.  This  substance  is  pulverized  and  mixed  with 
common  lime.'  " 

The  Silicate  Hydkaulic  Cement  in  the  Pkeven- 
TiGN  OF  Wall-Damp. 

In  laying  the  foundation  of  any  building,  the  mat- 
ter of  particular  consideration  should  be  the  thorough 
drainage  of  the  site,  and  next  to  that  complete  pre- 
vention of  wall-damp,  that  is,  the  rising  of  moisture 
by  capillary  attraction  or  otherwise,  in  the  heart  of 
the  brick  or  stone  work,  the  particulars  of  which 
have  been  lately  described  in  the  Manufactwrt  d' 
Builder's  Joui^nal^  to  which  the  author  had  added 
the  silicification  of  the  bricks  and  plaster.  It  states 
that  wherever  brickwork  comes  in  contact  with  the 
earth,  or  even  with  adjacent  walls  which  may  happen 
to  be  damp,  there  the  infection  is  certain  to  take,  and 
there  is  no  easy  cure  for  it,  if  once  it  makes  an  en- 
trance. 

The  readiest  remedy  in  all  cases  is  a  layer  of  fine 
concrete,  which  may  be  thinly  coated  on  the  top  with 
asphaltum  laid  on  hot.  This  done  all  around  the  top 
of  the  walls,  external  and  internal,  the  piers  and  every 
piece  of  brickwork,  that  in  any  manner  has  connec- 


82 


HYDRAULIC  LIMESTONE, 


tion  with  the  ground,  then  the  bricks,  which  ought 
to  be  specially  prepared  before  calcination  with  a  si- 
licate solution,  should  be  heated  over  charcoal  fur- 
naces and  their  beds  dipped  in  the  asphaltum  before 
being  laid.  It  is  evident  that  a  preventive  course 
could  thus  be  formed  above  ground  at  a  trifling  ex- 
pense, wholly  impervious  to  wall-dam,  at  the  same 
time  giving  a  bedding  to  the  superstructure  of  a  qua- 
lity very  far  superior  to  any  now  in  use.  Coating  the 
outside  face  of  the  walling  w4th  waterproof  silicated 
cement,  as  has  been  before  noticed,  is  only  the  safe- 
guard against  capillary  attraction  from  below,  and 
excluding  the  external  air  which  might  let  the  artifi- 
cial heat  of  the  rooms  to  attract  the  enemy  of  wall- 
damp.  It  is  known  that  common  brick  will  absorb 
1-5  of  its  weight  of  water,  and  where  the  storm  '  ^es 
the  rain  continually  against  the  face  of  a  wall  for  a 
sufficient  time  to  permit  the  interior  heat  to  attract 
it,  the  inside  of  the  wall  must,  of  necessity,  be  damp, 
and  the  papering  become  mouldy,  as  well  as  the  ceil- 
ing, will  next  be  rotten.  This  cause  of  wall-damp  is 
one  that  cannot  be  too  carefully  guarded  against,  as 
it  is  one  to  which  may  be  referred  the  early  decay  of 
many  residences,  as  well  as  the  inception  of  these 
pulmonary  symptoms  wdiich  so  surely  steal  away  the 
health  and  ultimately  the  life  of  many  a  victim. 

The  mortar  to  be  used  in  the  foundation  and  the 
wall  ought  to  be  very  well  prepared  so  as  to  possess 


CEMENTS,  ETC. 


85 


all  the  hydraulic  properties  and  silicification,  and 
caution  should  be  taken  in  not  using  sea  sand,  which 
will  certainly  create  the  damp  by  absorbing  all  the 
water  in  tlie  atmosphere,  this  being  the  chemical 
effect  of  its  saline  property. 

The  surface  of  the  walls  of  the  rooms  mnst  be  well 
attended  to :  the  plaster  of  Paris,  which  is  generally 
employed,  ought  to  be  properly  silicified,  so  as  ta 
prevent  the  absorbtion  of  the  natural  damp  of  the 
atmosphere  created  in  uninhabited  and  unheated 
rooms. 

It  is  preferable  to  paint  rooms  than  to  paper  them^ 
for  the  white  lead  and  linseed  oil,  with  a  little  lith- 
arge to  facilitate  the  drying,  becomes  hard  after  a 
short  time,  and  assists  the  fresh  plaster  wall  of  pre- 
venting the  admission  of  the  moisture;  as  the  fourth 
coating  of  white  lead  is  applied  with  equal  propor- 
tions of  oil  and  spirits  of  turpentine,  which  has  the 
property  of  being  very  volatile,  will  evaporate  en- 
tirely, leaving  the  surface  of  the  paint  of  a  very  com- 
pact and  hard  nature,  and  rendering  the  plaster  inca- 
pable of  absorbtion. 

Among  the  great  variety  of  cements  in  which  silica 
is  the  active  principal,  the  two  following  are  very 
useful  : 

1.  A  mortar  to  be  made  as  hard  as  any  cement, 
and  which  does  not  crack  in  setting,  and  even  of 
great  usefulness  as  hydraulic  cement  under  water, 


nYDEAULIC  LEVIESTONE, 


is  obtained  by  mixing  finely  slacked  lime  with  fine 
sand  [the  angular  grains  are  always  preferable  to  the 
round  grains  for  producing  a  good  mortar].  By  mix- 
ing the  sand  thus  prepared  with  finely  powdered 
■quick  lime,  and  stir  the  mixture  thoroughly.  During 
the  process  the  mass  heats,  and  may  then  be  em- 
ployed as  mortar,  to  which  has  to  be  added  one- 
eighth  of  the  mass  the  liquid  silicate  of  soda. 

One  part  of  good  slacked  lime  was  used  with  three 
parts  of  sand,  and  to  this  was  added  three-fourths  of 
its  weight  of  finely  powdered  quicklime  ;  the  mortar 
containing  one-eighth  of  the  liquid  silicate  of  soda  was 
then  used  as  a  foundation  wall,  and  in  four  days  had 
become  so  hard  that  a  piece  of  sharp  iron  would  not 
attack  it ;  and  in  two  months  afterwards  it  had  be- 
come as  hard  as  the  stones  of  the  wall. 

2.  A  thin  coating  of  slaked  lime  made  into  paste 
with  water  or  whitewash  is  put  at  once  on  the  stone, 
and  before  becoming  quite  dry  apply  the  silicate  so- 
lution over  the  paste,  by  which  the  mass  becomes 
completely  insoluble ;  a  petrification  takes  place  if 
applied  to  vegetable  substances,  decomposition  is 
prevented,  porous  building  stone  and  brick  are  pro- 
tected against  air  and  damp. 

Damp  Walls  and  Cellars. 

The  application  of  silicates  for  preventing  the 
penetration  of  rain  or  moisture  in  houses,  whereby 


CEMENTS,  ETC. 


85 


the  walls  are  absorbing  the  same,  and  render  the 
paper-hangings  or  delicate  paint  unfit,  so  as  to  de- 
stroy their  appearance,  has  been  amply  and  satisfac- 
torily proved.  The  silicates  of  soda  and  potash,  or 
either  of  them,  are  mixed  with  pure  white  lead  or 
zinc,  and  applied  soon  after  upon  the  walls,  which 
will  dry  immediately. 

The  presence  of  damp  in  walls  arises  from  three 
causes :  either  from  the  porous  condition  of  the  mate- 
rials of  which  they  are  built,  allowing  the  penetration 
of  damp  from  without ;  from  the  existence  of  salts 
in  the  mortar,  bricks  or  stone,  which  absorb  and  give 
out  moisture,  according  to  the  changes  of  the  wea- 
ther, or  from  damp  foundations.  The  first  only  can 
be  remedied  by  the  application  of  external  coatings, 
the  second  by  battening  the  walls,  and  the  last  by 
removing  the  adjacent  earth  from  the  foundations. 

As  has  already  been  stated  that  a  single  applica- 
tion of  a  paint  formed  with  lead  or  zinc  has  proved 
very  successful.  The  second  application  is  the  sili- 
cate solution  with  china  clay,  or  pure  alumina,  which 
has  the  advantage  of  not  drying  so  quick  as  that 
with  lead  or  zinc.  In  all  cases  the  paints  must  be 
put  on  uniformly,  so  that  the  whole  wall .  surface 
should  be  completely  covered  with  the  solid  coat, 
and  in  order  to  efi'ect  this  a  rough  stucco  surface, 
from  two  to  three  coats,  may  be  required.  It  is  found 

4 


86 


HYDRAULIC  LIMESTONE, 


also  useful  to  apply  tlie  second  coat  tliinner  than  the 
first. 

The  mixture  of  liquid  silicate  of  soda  with  clay 
and  that  of  whiting,  or  washed  carbonate  of  lime, 
may  probably  be  the  most  reliable  for  keeping  out 
damp  from  walls  as  well  as  cellars. 

On  applying  the  lead  or  zinc  as  the  first  coat, 
either  of  them  or  both,  it  may  be  done  in  the  follow- 
ing manner  ; 

Mix  them  with  a  little  water  and  lay  them  on  the 
stone,  they  w^ill  dry  very  soon  ;  apply  then  the  silicate 
solution  by  means  of  a  syringe.  If  the  application  is 
to  be  made  on  stone  which  shows  some  decay,  it  is 
necessary  to  remove  first  the  same,  apply  then  the 
aluminous  silicate  of  soda  (by  an  equal  mixture  of 
liquid  silicate  with  fine  white  clay),  and  then  apply 
the  carbonate  lime  and  silicate  w^ash  with  an  ordinary 
paint  brush,  stippling  it  so  as  to  give  it  the  appear- 
ance of  the  granulated  surface  of  the  stone.  When 
dry  it  will  adhere  sufiiciently  to  allow  of  other  washes 
of  silicates  being  brushed  on  it. 

The  conditions  necessary  for  success  are : 

1.  The  wall  should  be  coated  with  a  porous  mate- 
rial, such  as  lime  or  Portland  cement. 

2.  The  coating  must  be  perfect.  A  wall  wliich 
has  been  once  painted  is  altogether  unfit  for  any  ap- 
plication of  siliceous  washes,  for  the  reason  that  it  is 
not  absorbent  enough. 


CEMENTS,  ETC. 


8f 


The  best  ground  for  any  siliceous  work  is  lime  and 
sand.  In  new  buildings  it  would  be  better  to  use 
lime  and  sand  at  once,  and  then  to  cover  it  with  lime 
and  silicate  of  alumina  and  soda.  The  precipitated 
sulphate  of  baryta  may  safely  be  applied  in  the  sili- 
cate of  soda  for  all  the  above  purposes,  and  it  will 
produce  a  good  coating  and  a  fine  paint. 

Under  the  name  of  liquid  stone,  Fleury  describes 
the  application  of  the  alkaline  silicates  in  the  follow- 
ing manner : 

"  The  first  idea  that  suggests  itself  of  the  use  of 
such  a  liquid  is  the  preparation  of  artificial  stories 
for  ornamental  and  huUding  pvrjmes.  Should  it 
be  possible  to  produce  this  petrifying  liquid  clieap 
enough,  buihling-stones  in  all  their  variety  could  be 
made  and  cemented  together  with  the  same  jDctrify- 
ing  solution.  The  cost  of  cast  flint-marble  statuary, 
tombstones,  baths,  tables,  mantel-pices,  and  orna- 
ments of  all  kinds,  would  be,  of  course,  much  less 
than  if  laboriously  cut  from  the  stone,  and  they 
come  quickly  into  universal  use.  In  a  similar  way, 
as  photography  now  diffuses  the  masterpieces  of  the 
art  of  painting  among  all  classes  of  society,  and  cul- 
tivates their  taste,  the  art  of  casting  flint-marhle 
would  multiply  and  difiuse  the  masterpieces  of  sculp- 
ture, and  adorn  our  public  buildings,  gardens  and 
parks.  Bas-reliefs,  cameos,  cornices,  columns,  pillars, 
etc.,  might  be  produced   at   comparatively  cheap 


88 


HYDRAULIC  LIMESTONE, 


prices.  Should  the  liquid  be  of  a  kind  to  permit  its 
application  to  outside  or  inside  walls,  like  plaster, 
then  we  could  cover  our  brick  and  stone  houses  with 
white  or  colored  flint-marble  fronts,  and  our  churches, 
halls,  theatres,  parlors  and  rooms  with  glass-lihe  waU^, 
and  ceilings,  colored  ad  libitum  with  elegant  frescoes 
as  durable  as  the  still  fresh  paintings  at  Herculaneum 
and  Pompeii ;  while  the  floors  could  be  inlaid  with 
beautifully  colored  stones  in  mosaic  style. 

"  Another  important  application  for  such  a  liquid 
would  be  the  one  to  render  wood  non-inflaramdble^ 
rot  and  water-proof.  By  making  wood  non-inflam- 
mable, we  should  greatly  diminish  the  danger  to 
which  most  of  our  old  and  new  buildings  are  now 
exposed.  This  could  easily  be  effected,  and  with  not 
much  cost,  by  impregnating  the  wood  with  a  properly 
prepared  solution  of  flint ;  for,  if  once  the  pores  of 
the  wood,  which  by  their  capillary  action  cause  the 
communication  of  the  fire  to  the  whole  structure,  be 
stopped  up  by  the  incombustible  and  non-conducting 
silica,  the  wood  becomes  non-inflammable,  and  at  the 
same  time  proof  against  water  and  decay.  Not  less 
important  would  be  the  partial  silicificat!on  of  rail 
road-sleepers  and  cross-ties,  house,  ship  and  bridge 
timber :  they  would  be  stronger  and  last  longer. 
Telegraph-poles  would,  when  properly  treated,  be- 
come more  durable,  and  be,  in  addition,  better  non- 
conductors of  electricity.    What  a  new  field  would 


CEMENTS,  ETC. 


fBUch  a  petrifying  fluid  open  to  the  manufacture  of 
incombustible  paints  and  v^arnishes?  It  might  also 
be  mixed  with  paper  pulp,  or  cheap  vegetable  or  ani- 
mal fibre,  and  serve  for  the  manufacture  of  a  variety 
of  useful  articles,  such  as  staircases,  boxes,  trunks, 
soles  for  boots  and  shoes,  patterns,  moulds,  handles, 
parts  of  machinery,  pliotographic  instruments,  piano- 
keys  ;  and,  further-  it  might  be  used  as  a  coating  for 
preventing  the  oxidation  of  iron  or  other  metals. 
We  must  not  overlook  another  important  application 
in  the  use  of  the  liquid  flint — the  one  for  the  preser- 
vation of  old  monuments  and  stone  buildings.  It 
might,  perhaps,  also  serve  as  a  medium  for  the  pre- 
servation of  meat,  fruit,  vegetables,  eggs,  etc.  The 
linings  of  barrels,  for  oils  and  other  liquids,  the 
coating  of  tanks,  tubs,  sulphuric-acid  chambers,  etc., 
are  other  useful  applications  of  this  liquid. 

''Metallurgy  could  be  very  materially  benefited 
by  a  process  whereby  quartz  could  cheaply  and 
6pe3dily  be  dissolved  in  water ;  for  we  could  then 
take  the  gold  quartz  of  Nova  Scotia,  New  Hamp- 
shire, or  Canada,  and  dissolve  the  quartz,  and  obtain 
all  the  gold  as  a  precipitate.  Of  course,  as  the  liquid 
flint  could  be  used  for  so  many  useful  purposes,  and 
be  sold  for  a  good  price,  the  extraction  of  the  gold 
would  be  very  cheap,  and,  so  to  speak,  cost  less  than 
notliing,  as  the  extraction  price  of  the  gold  would  be 


90 


HYDRAULIC  LIMESTONE, 


more  than  paid  for  by  the  amount  realized  from  the 
sale  or  use  of  the  liquid." 

Hydraulic  Mortar  from  American  Limestone. 

These  limestones  contain  mostly  lime,  silica,  alu- 
mina, oxide  of  iron  and  magnesia,  which  form  the 
proper  materials  for  the  preparation  of  mortars;  they 
will  withstand  the  action  of  w^ater  and  moisture  bet- 
ter in  proportion  as  the  quantity  of  silica,  alumina 
and  magnesia  is  larger;  they  contain  40  per  cent, 
carbonate  of  lime,  30  per  cent,  carbonate  of  magne- 
sia, and  20  per  cent,  silica,  the  balance  is  alumina 
and  oxide  of  iron,  and  they  form  a  good  mortar  and 
a  good  building  material;  but  when  the  magnesia  i& 
too  prevalent,  will  deteriorate  it  for  building  pur- 
poses, it  being  too  friable.  The  dolomite,  which  is 
also  called  bitterspar,  a  magnesian  limestone,  is  a 
double  carbonate  of  lime  and  magnesia,  and  abun- 
dant in  the  United  States,  is  a  granular  limestone, 
and  a  hardness  of  3.5,  a  spec.  gr.  of  3.1,  and  consist- 
ing of  70  per  cent,  lime  and  nearly  40  per  cent,  of 
magnesia  and  some  oxide  of  iron  and  manganese,  is 
unlit  by  itself  as  a  building  material,  having  a  great 
tendency  to  crumble  into  small  fragments,  and  forms 
likewise  an  inferior  material  for  burning  and  con- 
verting it  into  cement,  because  it  lacks  the  silica  in- 
dispensable for  this  purpose.  By  an  addition  of  an 
^ilkaline  silicate,  either  the  silicate  of  potash  or  soda^ 


CEMENTS,  ET(\ 


91 


and  an  addition  of  some  alnmina,  will,  after  burning, 
produce  a  good  hydraulic  cement,  particularly  in 
such  localities  where  no  good  native  hydraulic  lime- 
stone is  found.  Not  alone  France  and  Germany  are 
particularly  rich  in  deposits  of  hydraulic  lime,  and  in 
the  United  States  likewise,  Imt  these  in  our  neighbor- 
hood may  be  particularly  mentioned  at  Kondout,  on 
the  western  shore  of  the  Hudson  Eiver,  100  miles 
distant  from  New  York.  The  quarrying  in  those 
subterranean  rocks  for  hydraulic  cement  and  also 
common  limestone  is  carried  on  in  that  region,  along 
a  large  extent  of  the  valley  of  the  Rosed  ale  River ; 
through  this  valley  the  Hudson  and  Delaware  Canal 
is  constructed,  which  brings  the  coal  from  the  Lack- 
awanna valley  at  Carbondale  directly  to  the  Hudson 
River.  This  coal  being  a  very  pure  anthracite  is  ad- 
mirably adapted  for  use  in  the  limestone  and  cement 
furnaces  situated  at  the  junction  of  this  canal  with 
the  Hudson  River. 

In  burning  hydraulic  limestone  not  only  the  car- 
bonic acid  and  water  of  hydration  are  drawn  off,  as  is 
the  case  with  common  limestone,  but  after  the  lime 
and  magnesia  have  parted  with  their  carbonic  acid, 
at  the  high  temperature  of  the  furnace,  they  act  on 
the  silica  and  alumina,  as  it  were,  like  two  powerful 
bases,  and  a  silicate  of  lime  and  magnesia,  as  also 
silicate  of  alumina  and  aluminate  of  lime,  are  formed. 
The  exact  chemical  reaction  during  the  burning  pro- 


HYDRAULIC  LIMESTONE, 


cess  is  however  as  yet  not  well  understood,  and  un- 
doubtedly varies  in  dilierent  limestones,  according  to 
their  chemical  constitution,  w^hich  latter  appears  also 
to  vary  considerably,  but  without  atfecting  mate- 
rially their  useful  properties. 

In  regard  to  the  theoretical  causes  of  the  harden- 
ing process,  which  takes  place  under  water,  it  may 
be  remarked  that  this  curious  and  interesting  pheno- 
menon, being  of  an  entirely  chemical  nature,  has 
largely  drawn  towards  itself  the  attention  of  eminent 
chemists,  who  have  attempted  to  explain  it  in  accord- 
ance with  well  known  chemical  laws.  All  hydraulic 
limestones  may,  by  the  ordinary  method  of  analysis, 
be  decomposed  into  tw^o  component  parts;  the  one 
consisting  of  the  carbonates  of  the  earth,  such  as 
lime,  magnesia,  etc.,  which,  like  ordinary  limestones, 
yield  a  fat  lime ;  the  other,  a  silicate,  or  rather  a 
mixture  of  the  silicates  of  alumina,  magnesia,  lime, 
and  sometimes  potassa,  as  we  find  in  the  felspar, 
w^hich  is  a  sili(;ate  of  alumina  and  potash,  and  a 
greater  or  less  excess  of  free  silica  ;  the  latter  consti- 
tuent is,  therefore,  simply  a  kind  of  clay.  The  reac- 
tion during  the  burning  process  has  been  already 
alluded  to.  Now  when  such  freshly  burnt  cement  is 
mixed  with  water,  the  excess  of  caustic  lime  as  well 
the  compound  into  which  the  siliceous  clay  has  been 
converted  during  the  burning,  react  upon  one  another 
in  sncli  a  manner,  that  a  solid  stone-like  silicate  is 


CEMENTS.  ETC. 


produced  in  the  humid  way,  the  water  has  a  double 
action,  dry  substances,  such  as  lime  and  silicate  of 
alumina,  do  not  act  one  upon  another,  unless  the  sol- 
vent power  of  water  is  brought  into  play  so  as  to 
bring  them  into  close  contact ;  the  water  transfers 
continually  the  lime  it  dissolves  to  the  silica.  The 
absolute  necessity  of  keeping  such  mortar  under 
water,  in  order  to  have  it  harden,  is  thus  explained. 
Another  action  of  the  water  is  this  :  it  enters  into  a 
state  of  hydration  in  the  silicate  of  lime  as  soon  as 
formed.  It  must  also  be  observed  that  the  molecula'l^ 
condition  of  the  silica  is  of  the  utmost  importance  in 
this  process.  Fine  sand  will  not  combine  with  lime, 
when  the  latter  is  dissolved  in  water  that  is  in  a  form 
known  under  the  name  of  limewater,  but  silica  preci- 
pitated from  a  soluble  glass  solution  by  means  of  an 
acid,  which  produces  the  gelatinous  form  of  silica, 
will  at  once  combine  with  the  lime  in  limewater  and 
form  a  silicate  of  lime.  The  silica  in  the  hydraulic 
mortar  is  also  in  a  state,  not  like  fine  sand,  but  che- 
mically combined  and  dissolved  in  the  mass,  and 
therefore  ready  to  combine  with  the  lime  in  lime- 
water.  Next  in  importance  to  silica  is  the  magnesia, 
which  renders  the  lime  hydraulic,  which,  according 
to  Fuch8,  has  been  proved  that  lime  and  magnesia 
well  mixed  will  harden  under  water  to  a  certain  ex- 
tent without  tlie  addition  of  silica;  for' we  have  in 
GeiTnany  a  hydraulic  lime  containing  only  4  per 


94 


HYDRAULIC  LIMESTONE, 


cent.  When  silica  is  found  to  the  extent  of  52  per 
cent.,  the  point  of  saturation  is  reached,  and  such 
limestone  is  no  more  hydraulic.  Alumina  and  iron 
may  be  entirely  absent,  although  the  former  is  always 
present  in  the  best  kinds  of  hydraulic  mortars,  of 
which  that  of  Rondout,  usually  called  Rosendale 
cement,  and  witli  the  employment  of  which  the 
Oroton  Water  Works  of  New  York  City  were  built, 
is  the  best  on  this  continent. 

^  It  is  confidently  to  be  hoped  that  by  the  proper  ap- 
plication of  alkaline  silicates  will  contribute  much 
to  the  manufacture  of  an  artificial  hydraulic  cement. 

Geeman  Hydkaulic  Cement. 

This  material,  artificially  prepared,  is  in  great  use 
and  is  of  very  peculiar  composition  :  unquestionably 
it  is  intended  to  form  a  silicate-aluminate  of  lime,  or, 
in  other  words,  an  argillaceous  silicate,  but  the  ad- 
mixture, such  as  charcoal  and  iron  filings,  cannot  be 
explained,  but  the  base  being  obtained  by  the  pro- 
duction of  an  alkaline  silicate  bespeaks  for  it  a  useful 
vehicle  as  a  cement. 

It  is  prepared  with  25  parts  common  clay,  60  parts 
lime,  10  parts  magnesian  limestone,  10  parts  iron 
filings,  and  10  parts  of  black  oxide  of  manganese ; 
these  materials,  in  very  fine  powders,  are  made  plas- 
tic by  the  liquid  silicate  of  soda,  at  once  applied  as  a 


CEMENTS,  ETC. 


95 


cement  or  mortar,  but  it  will  not  set  at  once,  six 
hours  being  required  for  the  mass  to  harden. 

Hardness  of  Ancient  Mortars. 

Mr.  Spillar  communicated  a  paper  on  this  subject 
to  the  British  Association,  in  1868,  of  which  the  fol- 
lowing are  the  conclusions,  from  the  chemial  exami- 
nation of  the  ancient  mortars  from  Burgh,  Pevesney, 
and  other  Roman  castles:  that  the  lime  and  carbonic 
acid  are  invariably  united  in  monatomic  proportions, 
as  in  the  original  limestone  rock  ;  and  that  there  is 
no  evidence  of  the  hydrate  of  lime  having  at  :.ny 
time  exerted  a  power  of  corroding  the  surfaces  of 
sand,  flint,  pebbles,  or  even  of  burned  clay,  with 
w^iich  it  must  have  been  in  contact  for  long  periods. 
Further,  that  the  water  originally  combined  with  the 
lime  has  been  entirely  eliminated  during  this  process 
of  recarbonation ;  and,  this  stage  passed,  the  amor- 
phous carbonate  of  lime  seems  to  have  been  gradu- 
ally transformed  by  the  joint  agency  of  water  and 
carbonic  acid  into  more  or  less  perfectly  crystallized 
deposits  or  concretions,  by  virtue  of  which  its  bind- 
ing properties  must  have  been  very  considerably  aug- 
mented. Messrs.  Abel  and  Bloxam  assign,  as  one  of 
the  causes  of  the  hardening  of  mortars,  the  formation 
and  subsequent  crystallization  of  the  carbonate  of 
lime. 

Stinde  proposes  the  silicate  as  a  very  useful  ce- 


96  HYDRAULIC  LIMESTONE, 

ment  by  mixing  equal  parts  of  oxide  of  manganese 
and  oxide  of  zinc,  and  making  them  into  a  thinnisli 
paste  with  the  silicate  of  soda,  which  paste,  quickly 
applied,  sets  very  rapidly ;  and  by  mixing  the  hy- 
draulic lime  to  this  composition,  it  is  a  cement  which 
will  resist  permanently  also  the  action  of  water  and 
heat : 

"  Cement  and  Moetar  of  the  Ancients. 

"  We  all  know  how  enthusiastic  some  are  in  their 
j^raises  of  those  ancient  structures  which  have  re- 
sisted for  ages  the  ravages  of  time.  They  imagine 
that  they  are  at  liberty  to  draw  conclusions  which 
are  not  the  most  favorable  to  the  architecture  of  the 
present  time.  Although  they  may  be  in  a  measure 
correct,  it  can  not  be  denied  that  such  critics  are  too 
partial  in  their  admiration  for  things  ancient  as  op- 
posed to  things  modern.  We  frequently  hear  the 
remark  that  some  of  the  Roman  mortars  have  en- 
dured for  eighteen  centuries  the  vicissitudes  of  time, 
while  many  buildings  of  now-a-days  present,  in  a 
very  brief  period,  the  sign  of  quick  decay ;  but  they 
forget  that  these  ancient  buildings  constitute  an  ex- 
ceedingly small  fraction  of  the  enormous  number  of 
those  erected  during  many  centuries  in  Egypt,  Greece, 
Rome,  and  her  provinces.  They  do  not  consider  that 
thousands  of  temples,  palaces,  and  private  dwellings 
have  been  entirely  destroyed.  And  what  answer  can 


CEMENTS,  KTG. 


97 


tkey  assign  to  the  faet  that  the  very  com  plaints  they 
indulge  in  were  even  more  frequent  then  than  now  ? 
Pliny  asserts  that  the  reason  of  the  falling  in  of  many 
buildings  in  Home  was  to»be  attributed  to  the  fact  of 
the  bad  quality  of  the  mortar. 

"  Still  more  important  than  this  argument  is  that 
of  Vitruvius,  the  architect  of  Augustus.  He  has  left 
a  work  on  Romai!  architecture  in  which  we  find 
nothing  that  entitles  us  to  place  the  architects  of 
antiquity  above  those  of  the  present  time.  Again, 
it  has  not  been  taken  into  account  that  a  great  part 
of  the  extraordinary  strength  of  antique  architecture 
is  more  the  effect  of  time  than  the  mechanical  skill 
of  the  builder,  or  the  virtues  of  his  cements,  as  we 
propose  to  show  hereafter.  Pliny  and  Yitruvius  both 
ex])lain,  to  the  best  of  their  knowledge,  what  kind  of 
materials  the  builders  selected  for  their  cements,  and 
how  they  were  prepared.  The  process  was  identical 
witli  the  modern  modus  operandi.  It  is  true  that  the 
old  Tlomans  were  particularly  careful  in  tlie  selection 
of  materials  for  their  mortar,  as  well  as  in  its  prepa- 
ration. They  were  aware  that  they  must  calcine  the 
limestone,  and  mix  it  with  sand,  in  order  to  apply  it ; 
but  did  not  possess  any  correct  idea  of  the  change 
whicli  limestone  undergoes  in  the  process  of  calcina- 
tion, nor  of  that  which  is  the  cause  of  the  cohesive 
quality  of  mortar. 

"  Many  centuries  elapsed  before  these  facts  were 


98 


HYDRAULIC  LIMESTONE, 


understood  and  explained.  Black,  in  1Y57,  started 
the  explanatory  theory  by  the  discovery  of  carbonic 
acid.  A  few  years  previous  to  this,  Marggraf,  the 
discoverer  of  sugar  in  beets,  found  the  elements  of 
gypsum,  which  was  already  employed  by  the  Eomans  ; 
and,  in  1768,  Lavoisier  demonstrated  the  causes  of  the 
hardening  of  burnt  gypsum  when  it  is  mixed  with 
water. 

"  The  ancients,  therefore,  put  their  practical  know- 
ledge to  the  best  possible  account.  As  they  were  de- 
ficient in  chemical  knowledge,  they  were  guided  only 
by  what  observation  taught  them.  Their  chief  care 
was  centred  in  the  exterior.  In  the  selection  of  lime- 
stone, the  color  decided.  The  white  ones  were  con- 
sidered best,  and  the  colored  ones  were  seldom  used. . 
Those  taken  from  the  interior  of  the  earth  w^ere  pre- 
ferred to  the  stones  which  were  met  with  upon  the 
shores  of  rivers.  A  law  provided  that  the  lime  must" 
have  been  slacked  three  years  before  it  could  be  used. 
The  same  also  prescribed  the  quantity  of  sand  which 
must  be  mixed  with  the  lime,  mentioning  also  that 
crushed  cherts  imparted  a  greater  strength  to  the 
mortar.  Its  preparation  was,  as  it  were,  a  state  affair, 
the  censors  watching  carefully  over  it.  In  spite  of  all 
this,  it  often  happened,  as  Pliny  states,  that  they  did 
not  attain  the  object  in  view. 

"  But  in  the  advance  of  chemical  science,  the  fact 
has  been  established  that  a  mortar  can  be  prepared 


CEMENTS,  ETC. 


that,  in  the  course  of  one  or  two  years,  will  be  a& 
strong  and  durable  as  Roman  mortar  after  the  lapse 
of  two  thousand  years.  The  builders  of  tjie  ancients 
were  not  farther  advanced  than  those  of  the  middle 
ages.  The  walls  of  the  Bastile,  for  instance,  were  so 
strong  that  they  had  to  be  blasted  away.  This  iiad 
likewise  to  be  done  in  the  removal  of  the  remnants 
of  a  bridge  at  Agen-,  built  about  the  year  1200  ;  and 
the  mortar  of  a  bridge  erected  at  Cahours  in  1400 
was  even  found  to  be  considerably  stronger  than  that 
of  the  antique  tlieatre  of  the  same  city. 

"  The  Romans  were  also  acquainted  with  hydraulic 
cement.  The  merit  of  this  knowledge  is,  however, 
considerably  lessened  when  we  consider  that  the  same 
is  found  in  the  volcanic  districts  of  Southern  Italy. 
A  mere  accidental  observation,  the  same  being,  per- 
haps, mixed  with  sand  instead  of  lime,  may  have  led 
to  its  application.  Says  Yitruvius :  'There  exists  a 
kind  of  dust  which  produces  strange  things;  it  is 
found  near  Baja  and  the  Vesuvius.  When  mixed 
with  lime,  it  forms  a  mortar  which  not  only  imparts 
great  strength  to  buildings,  but  also  to  water  works.' 

"  The  natural  cement  in  question  is  a  volcanic 
pumice-stone,  like  breccia,  which  is  still  found  in 
the  environs  of  Naples.  At  a  less  remote  period  of 
time,  when  the  Romans  invaded  the  valleys  of  the 
Lower  Rhine,  they  easily  recognized  the  volcanic 
nature  of  the  Brohl  Yalley.    Here,  as  well  as  amid 


100  HYDBATTLIC  LtM^^TONE, 

the  surroundings  of  the  beautiful  Laacher  Lake, 
which  lies  like  a  jewel  set  in  the  midst  of  the  long- 
extinct  Rhenish  volcanoes,  they  discovered  another 
natural  cement  —  the  trass  —  in  such  considerable 
quantities  that  the  quarries  which  were  opened  at 
that  time  are  still  in  existence.  The  use  of  hydraulic 
cement  in  ancient  times  could,  therefore,  have  been 
only  a  limited  one,  as  it  was  found  only  at  the  two 
places  mentioned.  Its  artificial  preparation  was  not 
understood.  The  solution  of  this  problem  was  re- 
served for  the  investigating  minds  of  the  present  pro- 
gressive century." 

"  Hydraulic  Cement. 

This  material  is  justly  esteemed  far  superior  to 
metal  of  any  description  for  the  lining  of  cisterns,  the 
water-proofing  of  cellar-bottoms,  and  similar  pur- 
poses. A  few  directions  for  its  preparation  and  use 
may  not  be  out  of  place.  To  make  water-proof 
work,  it  must  be  borne  in  mind  that  common  lime 
must  not  be  used  at  all;  for  on  common  lime  water 
or  moisture  has  an  effect  just  the  opposite  to  that 
which  it  has  on  the  water  lime^  rendering  it  soft  and 
quite  friable  when  dried ;  whilst  on  the  water-lime 
the  well-known  effect  is  to  make  it  perfectly  liard. 
JS^o  mixture  of  these  two  varieties  of  lime  can,  there- 
fore, be  made  under  water.  But,  although  they  do 
not  act  well  together  even  under  ground,  they  serve 


CfiMENTS,  ETC. 


101 


well  in  dry  places,  such  as  buildings  whose  walls  are 
of  extra  thickness  ;  and  if  proper  care  be  taken,  they 
will  conjointly  form  a  very  compact  and  powerful 
cement.  The  fact  that  water-lime  shrinks  when  wet, 
while  common  lime,  in  the  same  state,  swells,  at  once 
points  out  the  manner  of  treatment  to  be  pursued  in 
uniting  the  two  thoroughly.  Thus,  it  is  necessary  to 
ascertain  the  per  centage  of  shrinking  of  the  one  and 
increase  in  the  other,  as  nearly  as  possible,  before  the 
proportion  of  one  to  the  other  can  be  determined, 
with  a  view  to  their  intimate  combination.  Such 
experiments  are  the  more  necessary  when  we  consider 
the  great  difference  which  exists  in  the  quality  of 
both  kinds  of  lime  in  various  localities.  The  simplest 
and  most  effectual  mode  of  testing  water-lime  is  to 
put  several  portions  of  different  makes  into  small 
bags  of  flannel,  and  throw  them  into  a  basin  of  water. 
After  three  minutes'  immersion,  take  them  all  out  at 
once,  and  squeeze  each  in  the  hand.  Then  take  off 
each  bag,  and  that  which  is  best  h  firmest,  and  when 
thrown  naked  into  the  water  again,  loses  least  of  its 
outer  coat.  If  none  of  them  will  bear  uncovering  at 
three  minutes,  try  four,  five  minutes,  but  this  latter 
should  be  the  longest  test.  The  test  for  common  lime 
is,  on  the  contrary,  the  bursting  open  and  evolving  of 
caloric  in  a  greater  or  less  degree ;  and  the  conse- 
quent action  of  the  water  will  show,  by  its  bubbles, 
the  power  of  the  lime. 


102 


HYDRAULIC  LIMESTONE, 


"  It  is  the  per  centage  of  clay  contained  in  any  spe- 
cimen of  lime  that  determines  'the  solidifying  pro- 
perty of  the  cement  made  from  it.  The  best  hydrau- 
lic lime  contains  silex,  lime  and  magnesia,  or  alumina. 
Its  solidification  is  attributable  to  the  formation  of 
silicate  of  alumina  and  lime,  'or  of  magnesia  and 
lime,  which  combines  with  water,  and  produces  a 
hydrate  excessively  hard  and  insoluble  in  water. 
The  hardening  of  hydraulic  lime  may,  then,  be 
compared  to  that  of  calcined  plaster,  which  also 
coiabines  with  water  to  form  a  solid  hydrate ;  which 
calcined  plaster,  from  the  large  quantities  of  it  man- 
ufactured near  that  city,  is  commonly  known  as 
Plaster  of  Paris.  A  limestone  containing  thirty 
per  cent,  of  clay  makes  a  quick-setting  cement ;  and 
we  have  in  the  United  States  the  Rosendale  and  the 
Bellville  cements,  having  forty  and  fifty  per  cent. 
They  become  exceedingly  hard  when  plunged  in 
water  for  from  two  to  three  minutes.  Both  these 
cements,  especially  the  former,  have  been  used  ex- 
tensively by  our  engineers. 

"  Inferiority  in  the  quality  of  hydraulic  lime  may 
be  produced  by  the  want  of  proper  care  during  its 
manufacture,  the  stone  being  calcined  at  too  high  a 
temperature ;  the  double  silicate  in  such  case  becom- 
ing a  sort  frit,  which  does  not  hydrate  in  contact 
with  water. 

"  As  hydraulic  lime  is  expensive,  according  to  the 


CEMENTS,  ETC. 


105 


distance  of  its  transportation,  we  will  here  give  the 
method  of  making  an  artificial  hydraulic  lime,  accord- 
ing to  the  highly  successful  experiments  of  M.  Yicat 
a  celebrated  French  engineer  and  the  author  of  a 
much  esteemed  work  on  hydraulic  cement,  who  first 
pointed  out  the  method  to  be  adopted  in  its  forma- 
tion. It  is  prepared  by  stirring  into  water  a  mixture 
of  one  part  of  clay  and  four  parts  of  chalk  ;  these 
materials  should  be  mixed  by  a  vertical  wheel  turn- 
ing in  a  circular  trough,  and  made  to  flow  out  into  a 
large  receiver.  A  deposit  soon  takes  place,  which  is 
formed  into  small  bricks,  which,  after  being  dried  in 
the  air,  are  moderately  calcined.  Hydraulic  lime 
thus  prepared  enlarges  about  two-thirds  in  volume 
when  placed  in  water.  Like  the  natural  hydraulic 
lime,  it  can  be  completely  dissolved  by  acids.  This 
invention  of  artificial  hydraulic  lime  has  rendered 
Vicat  deservedly  famous,  as  it  has  been  in  use  for 
many  years  in  the  public  works  throughout  France, 
and  was  even  employed  in  the  hydraulic  masonry  of 
the  St.  Martin  canal.  That  it  can  be  made  in  this 
country  there  is  no  doubt,  as  the  argillaceous  or  pot- 
ter's clay  required  is  to  be  found  almost  everywhere^ 
The  new  cement  which  M.  Sorel  proposed  to  the 
French  Academy  consists  in  the  application  of  a 
basic  hyd rated  oxycliloride  of  magnesium,  may  un- 
questionably be  improved  by  means  of  a  silicated 
hydraulic  lime  and  the  bittern  of  the  salines,  which 


104 


HYDRAULIC  LIMESTONE, 


is  a  ehloride  of  magnesium  in  a  concentrated  con- 
dition. 

Lime,  sand  and  clay,  when  mixed  with  water,  form 
the  so-called  composition  of  a  hydraulic  cement : 
they  are  fit  to  unite  solid  surfaces  by  hardening  after 
a  few  days  application,  under  water,  by  forming  a 
combination  with  the  constituents  of  either  surface. 
Walls  and  piers  have  been  built  for  over  one  hundred 
years,  and  after  being  exposed  under  water  have  be- 
come harder  and  harder.    This  cement  is  also  called 
Eoman  cement,  because  the  natural  materials  are 
found  in  abundance  in  the  Eoman  district  where  the 
tufas,  puzzuolanas  and  trass,  all  products  of  volcanic 
districts,  like  the  Pontine  Marshes  of  Rome,  and 
near  Naples,  are  abundant,  and  consist  of  those  ele- 
mentary substances.    In  the  volatic  formations  of 
the  triassic  period  the  marls  or  green  sand,  the  cu- 
rious nodular  and  lenticular  concretions,  the  Septa- 
rias  and  Indus  Ilelmontii,  of  turtle  shape,  all  found 
in  argillaceous  strata  of  the  sedimentary  rocks  which 
are  alternating  with  limestone  beds,  and  all  found  in 
abundance  on  the  English  and  French  coasts  and  the 
United  States,  all  of  them  form  a  siliceous  clay  inter- 
mixed with  lime,  and  are,  therefore,  the  proper  mate- 
rial for  a  hydraulic  lime  or  cement;  the  Portland 
cement  is  largely  manufactured  at  the  mouth  of  the 
Thames,  the  Roman  is  also  manufactured  in  England 
from  the  materials  or  nodules  picked  up  or  found  in 


CEMENTS,  ETC. 


105 


the  cliffs  near  Harwich ;  the  septarias  are  from  the 
London  clay,  and  yield  good  cement.  The  marls  of 
New  Jersey,  which  are  called  green  sand,  occur  in  a 
large  belt  of  cretaceous  rocks,  have  of  late  years 
been  of  great  importance  to  the  Jersey  farmers, 
and  have  a  similar  composition  of  lime,  silica  and 
clay  forms,  all  excellent  materials  for  a  hydraulic 
cement. 

This  cretaceous  belt  with  its  clay  as  a  foundation 
and  boundless  supplies  of  silica  forms  the  most  pro- 
ductive strip  of  country  and  is  well  worth  the  con- 
sideration of  a  reflecting  mind  and  the  manufacturers 
of  these  substances.  Most  of  tlie  above  materials 
contain  about  70  procent  Lime,  20  procent  clay,  and 
20  procent  silica,  which  when  calcined,  the  Lime  be- 
comes caustic  and  forms  with  the  silica  and  clay  a 
double  silicate  of  this  form  such  as  CaO — CO3,  SiO,, 
Al  O3  H.  O. 

The  Portland  cement  is  exported  largely  trom 
England  and  according  to  the  manufacturers  name  is 
called  Reess,  Hamilton  and  other  cements  and  will 
bear  a  strength  varying  from  20 — 60ft>  to  the  square 
inch. 

The  celebrated  french  cement  of  Bouilly  is  prepared 
in  Boulogne  from  the  pebbles  called  Golets  which  are 
nodules  found  in  that  region.  The  Terra  Cotta  is  also 
a  cement  of  clay  and  silica. 

Silicate  of  soda  or  potash  may  be  mixed  with  the 


106 


HYDRAULIC  LIMESTONE, 


particles  of  any  material  or  body,  sucli  as  common 
sand,  dust,  sawdust,  clay,  chalk,  marble-dust,  metal- 
filings,  etc. ;  a  paste  may  be  formed  of  the  same, 
which,  in  a  short  time,  will  become  hard  and  tena- 
€ious.  Common  clay  thus  mixed  forms  a  fine  and 
plastic  mass,  and  becomes  very  hard.  Saw-dust  can 
be  formed  into  any  shape,  acquires  considerable 
strength  combined  with  lightness,  and  has  been  pro- 
posed as  an  excellent  non-conductor  of  heat.  A 
€ake  of  the  same  five-eighths  of  an  inch  thick  may 
be  placed  on  a  white-hot  iron  for  half  an  hour,  and 
while  its  under  side  in  contact  with  the  iron  will  get 
charred,  the  upper  side  will  get  but  little  warmed. 

The  adhesion  of  all  these  various  pastes  to  glass, 
minerals  and  metals  is  most  remarkable,  but,  unfortu- 
nately, all  of  them  except  those  formed  with  the 
carbonates  of  lime  and  some  woods,  do  not  resist 
humidity  or  water.  However  hard  any  article 
formed  of  sand,  clay,  etc.,  and  silicate,  may  have 
become,  however  dry  and  old,  the  same  is  soon  dis- 
solved or  reduced  to  its  component  parts  when  com- 
ing into  contact  with  water,  or  when  exposed  to 
humid  air. 

The  combination  of  the  silicates  with  the  carbon- 
ates of  lime  form  a  remarkable  exception  to  the 
above.  After  the  lapse  of  a  comparatively  short 
time,  the  objects  formed  of  a  paste  of  the  same  and 
silicate  become  hard  and  perfectly  indissoluble  in 


CEMENTS,  ETC. 


lOT 


cold  or  hot  water,  and  will  resist  humidity  and 
weather.  But  their  propert}^  to  adhere  to  metals, 
more  especially  to  iron,  is  so  remarkable  that 
the  idea  suggested  itself  to  use  the  same  as  a 
coating  for  iron,  either  merely  for  ornamental  })ur- 
poses,  for  protection  against  rust  or  fire,  etc.  A 
series  of  experiments  and  tests  fully  proved  the  prac- 
ticability of  the  process,  and  a  patent  was  ap])lied 
for  and  granted  to  B.  Oertly  and  X.  Fendrich  for 
the  same. 

This  coating  of  iron  with  marble  and  silicates,  it 
may  safely  be  said,  constitutes  one  decided  step  for- 
ward in  the  use  of  silicates,  and  even  of  iron. 
While  offering  the  most  comprehensive  protection 
to  iron,  the  coating  is  susceptible  of  any  coloring 
and  of  any  finish  of  marble.  Iron  columns,  espe- 
cially wrought-iron  columns,  can  thus  be  rendered 
beautiful,  while  receiving  additional  security  in  cases 
of  fire  from  the  low  power  of  conducting  heat  of  the 
coating.  Table  plates,  billiard  plates,  counter  tops, 
doors  or  door-panels,  shutters,  etc.,  while  vicing  in 
appearance  with  stone,  are  rendered  strong  by  their 
iron  skeleton.  In  connection  with  saw-dust  the 
coating  forms  the  best  coating  for  boilers  and  steam- 
pipes.  As  the  co-efficient  of  contraction  and  expan- 
sion of  the  coating  is  almost  identical  with  that  of 
iron,  exposure  to  heat  and  to  great  differences  of 
temperature  will  not  injure  its  sticking  qualities. 


108 


HYDKADLIC  LIMESTONE, 


and  this  singular  quality  of  the  coating  really  con- 
stitutes its  excellence. 

The  science  of  heating  and  ventilating  public  and 
private  buildings  has  been  extensively  investigated 
and  discussed  for  the  last  thirty  years,  and  not  with- 
out many  practical  and  beneficial  results.  The  me- 
chanical laws  governing  the  subject,  if  no  better 
understood  than  in  the  days  of  Peclet,  are  more 
generally  hseded.  The  chemical  constitution  of 
fresh  and  pure  air,  of  vitiated  or  contaminated  air, 
has  been  ascertained  by  the  most  refined  methods, 
in  the  valley,  on  the  mountain,  in  town  and  coimtry, 
in  the  bed-room  and  public  hall,  almost  all  over  the 
globe.  An  endless  number  of  hot-air,  hot-water,  or 
steam-heating  systems,  of  more  or  less  or  no  value 
or  merit,  are  at  the  choice  of  the  wealthy,  but  no 
devices  have  until  now  been  suggested  to  improve 
the  means  of  heating  the  dwellings  of  the  mass  of 
the  people.  The  iron  stove  forms  as  yet  the  great 
and  simple  apparatus  for  warming  the  inhabitants 
of  the  million,  and  from  its  cheapness,  its  portability, 
and  its  elastic  adaptability  to  ditferences  of  tempera- 
ture of  a  wide  range,  continued  to  be  the  great 
means  of  heating  the  homes  of  the  people.  And 
indeed,  if  we  are  to  believe  the  graphic  accounts  of 
a  more  recent  lecturer  and  professional  engineer  of 
ventilation,  (L.  W.  Leeds,  Esq.,)  it  must  also  be  re- 
garded as  a  providential  protection  of  the  people, 


CEMENTS,  ETC.  109 

that  the  introduction  of  those  hot-air  devices  could 
not  become  more  general. 

To  correct  or  ameliorate  the  obvious  defects  of  the 
iron  stove  by  means  at  once  cheap  and  easy  appli- 
cable, is  the  object  of  the  invention  now  brought  to 
your  notice.  Acknowledging  the  great  importance 
of  ventilation,  it  is  not  proposed  to  interfere  with 
that  question,  which  moreover  cannot  be  considered 
settled  or  ripe  for  a  popular  formula  when  such  great 
discrepancies  occur  in  the  precepts  of  the  most  in- 
defatigable investigators,  and  when  the  air  in  the 
halls  of  Congress,  though  renewed  twelve  times  an 
hour,  and  having  a  purer  chemical  constitution  than 
the  air  of  the  Alps,  is  nevertheless  considered  op- 
pressive by  our  national  legislators. 

The  defects  of  the  iron  stove  are  well  known — 
excessive  heat  one  hour,  deficiency  of  such  the  next 
hour,  burning  of  the  air,  waste  of  fuel,  etc.  Per- 
haps nowhere  are  these  defects  more  apparent,  more 
oppressive,  and  more  dangerous,  than  in  the  iron 
stoves  of  our  railroad  cars.  Though  many  improve- 
ments have  been  made  in  iron  stoves,  it  is  certainly 
a  patent  fact  that,  in  a  great  majority  of  cases,  espe- 
cially during  the  severer  portions  of  the  winter  season, 
the  iron  stove  is  allowed  to  become  red-hot  until  the 
heat  emanating  from  it  does  become  unbearable  and 
dangerous,  when  of  a  sudden  the  stove-door  is  thrown 
open  and  draft  shut.    The  red-hot  iron,  being  of  a 

5 


110  HYDRAULIC  LIMESTONE, 

temperature  about  1,000^  F.,  decomposes  or  burns 
the  organic  particles,  gas,  or  even  animalcules,  vdiich 
float  in  ordinary  atmospheric  air,  to  a  greater  or 
lesser  extent,  and  which  are  exhaled  from  the  human 
body.  Air  thus  acted  upon  must  become  disagree- 
able and  offensive,  if  not  positively  injurious.  A 
serious  waste  of  fuel  does  also  take  place  by  the 
above  method  of  heating.  The  air  of  the  room, 
when  the  stove-door  is  open,  is  heated  over  the  burn- 
ing fuel,  and  escapes  through  the  stove-pipe  without 
contributing  anything  to  heating  the  room,  and  the 
balance  of  the  air,  heated  by  the  lower  and  hottest 
parts  of  the  stove,  follows  the  same  line ;  the  draft 
being  shut  off  or  checked,  but  a  small  portion  of  air 
finds  access  to  the  heated  coal,  and  on  account  of  the 
great  preponderance  of  incandescent  carbon  over  the 
supply  of  oxygen,  the  combustion  does  not  take 
place  by  producing  carbonic  acid  C  O,  but  by  pro- 
ducing oxide  of  carbon  C  O  ;  a  fact  well  established 
by  chemists.  This  form  of  combustion,  while  con- 
suming the  same  amount  of  fuel,  produces  but  one- 
quarter  (^)  of  the  caloric  which  is  produced  when 
carbonic  acid  C  O  is  formed,  that  is,  when  a  full 
supply  of  oxygen  or  fresh  air  is  furnished  to  the 
burning  fuel,  as  is  the  case  with  stove-door  shut  and 
draft  open.  The  combustion  is  retarded,  not  as 
might  be  supposed,  by  spreading  the  same  amount 
of  caloric  over  a  longer  period  of  time,  but  by  ac- 


CEMENTS,  ETC. 


Ill 


tualiy  reducing  its  measurable  amount  to  one-quarter 
of  that  due  to  the  consumed  fuel  when  properly 
burned.  Some  of  tlie  oxide  thus  formed  will  find 
its  way  into  the  room,  where  its  presence  is  by  far 
more  dangerous  than  a  large  amount  of  carbonic 
acid,  it  bsing  a  positively  acting  poison. 

The*  stove  now  offered  for  the  first  time,  and  for 
which  a  patent  w^as  granted  to  B.  Oertly  and  X. 
Fendrich,  on  the  18th  of  August,  1808,  obviates  or 
remedies  the  above  defVcts  in  toto.  It  will  be  but  a 
trifle  more  expensive  than  the  common  iron  stove  ; 
will  be  as  portable  as  the  latter ;  will  require  as  little 
extra  mechanical  skill  in  its  setting  and  handling, 
while  it  substantially  has  all  the  advantages  of  the 
porcelain,  the  soap-stone,  the  sand-stone,  etc.,  stoves, 
and  excels  them  all  in  the  finish  it  is  susceptible  of. 

The  mass  of  silicate  and  minerals,  either  applied 
as  coating  to  cast-iron  or  wrought-iron  stoves,  or 
forming  exclusively  the  body  of  a  stove,  with  or 
without  an  iron  framework  embedded  in  it  for  pur- 
poses of  strength,  radiates  heat  by  far  more  freely 
than  iron,  while  its  conductive  powers  to  that  of  iron 
are  in  the  ratio  of  16  to  27.  Its  superior  radiating 
powers  over  those  of  iron  can  be  readily  tested  and 
ascertained  by  any  ordinary  thermometer.  It  dif- 
fuses a  pleasant  and  sufficient  heat  at  a  temperature 
at  which  iron  scarcely  makes  itself  felt,  except  by 
immediate  contact,  and  thus  allows  of  a  sufficiently 


112 


HYDRAULIC  LIMESTONE, 


rapid  transmission  of  heat  to  warm  an  enclosed  space 
without  assuming  itself  such  a  high  temperature  as 
to  burn  or  decompose  any  organic  gases  or  particles 
floating  in  the  air  of  any  occupied  room,  and  all  of 
this  while  admitting  the  most  favorable  circum- 
stances for  a  full  combustion  of  the  fuel.  Fresh  air 
for  ventilation  can,  and  ouglit  to  be,  introduced  in 
the  various  manners  it  is  now  introduced  in  connec- 
tion with  iron  or  porcelain  stoves.  The  invention 
accomplishes,  at  less  cost,  all  of  what  the  most  im- 
proved earth  en  w^  are  or  soap-stone  stoves  of  the  pre- 
sent day  accomplish. 

Kuhlmann,  in  his  theoretical  view  on  the  beha- 
viour of  the  alkaline  silicate  towards  the  artifi- 
cial production  of  hydraulic  lime,  cements  and 
silicified  stones,  says  of  the  artificial  hydraulic  lime 
as  follows:  If  w^ater  is  mixed  with  slaked  rich 
lime  and  a  solution  of  a  Potash  or  Soda  silicate, 
the  Potash  or  Soda  are  separated  and  the  silica 
combines  with  the  lime  in  place  of  a  part  of 
the  water,  which  saturated  the  same  and  forms 
a  paste,  capable  of  disseminating  in  the  fluid  to 
all  extend.  This  combination  renders  the  lime 
plastic,  which  when  exposed  to  heat  and  put  into 
water,  will  keep  clear.  All  particles  of  lime  are 
60  to  say  luted  by  the  silica  cement.  This  lime 
if  combined  with  a  basic  silicate  and  exposed  to 
atmospheric  air,  attracts,  if  in  buildings,  carbonic 


CEMENTS,  ETC.  113 

acid  which  by  degrees  is  converted  into  silicate  of 
lime. 

Similar  products  are  obtained  by  substituting 
aluminates  of  these  bases  to  the  Potash  or  Soda  sili- 
cates. 

The  Sillification  of  the  Mortar  from  Fat  Lime. 

If  walls  are  moistened  with  the  solutions  of  the 
silicates,  a  reaction  takes  place  at  once  to  convert  the 
hydrate  of  lime,  no  matter  how  old  the  same  was,  into 
a  lime  silicate,  whereby  a  part  of  the  Potash  or  Soda 
are  separated ;  the  silicate  which  may  have  been 
bound  to  the  carbonate  of  lime,  forms  a  new  com- 
bination analogous  to  that  hydraulic  mortar,  produced 
artificially  by  the  moist  way.  If  the  alkaline  silicate 
is  in  excess,  the  reaction  on  the  carbonate  goes  on 
according  to  the  property  described.  The  silification 
of  porous  limestones  is  explained  in  this  manner : 
The  native  carbonate  of  lime,  if  coming  in  contact 
with  the  potash  or  soda  silicate,  acts  partially  like 
caustic  lime.  Potasli  and  soda  are  separated  by  the 
contact  of  the  alkaline  silicate,  and  the  silica  forms 
the  same  carbonated  silicate,  like  that  formed  in  the 
above  manner. 

In  support  of  this  explanation  must  be  stated,  that 
the  alkalis  potash  and  soda  are  in  all  cases  rendered 
caustic,  and  that  the  chalk  must  withdraw  the  last 
trace  of  the  silica  by  the  boiling  it  with  the  soluble 


114 


HYDRAULIC  LIMESTONE, 


alkaline  silicates,  and  invariably  retaining  the  car- 
bonic acid  in  the  composition.  It  is  clear,  there- 
fore, that  the  carbonates  of  lime  exercise  a  basic 
effect  in  the  presence  of  silica,  which  is  retained 
by  the  potash  or  soda  through  some  affinities.  It 
is  likewise  obvious  that  these  phenomena  so  indi- 
cate the  invariable  result  of  the  formation  of  a 
hydrated  silico  carbonate  of  lime,  which  is  capable 
of  parting  with  its  water  by  degrees,  and  to  assume 
the  characteristic  hardness  of  hydraulic  cements. 
The  silification  of  gypsum  is  thus  explained :  The 
effect  of  the  soluble  silicates  on  gypsum,  in  plaster 
of  Paris,  is  materially  different  from  that  which  the 
silicates  perform  on  lime.  In  a  practical  point  of 
view,  its  results  are  unreliable  and  difficult  to  pro- 
duce. The  alkaline  silicates  undergo  a  decompo- 
sition if  coming  in  contact  with  sulphate  of  lime, 
they  form  a  sulphate  instead  of  a  silicate. 

It  is,  however,  known  that  sulphate  of  soda,  on 
account  of  its  crystalization,  has  a  tendency  of  de- 
stroying the  porous  limestones,  and  it  is  therefore 
used  to  test  the  weather-worn  stones ;  it  is  advisable 
to  use  a  potash  salt  if  intended  for  hardening 
gypsum.  Another  important  circumstance  is  in  the 
application  of  the  alkaline  silicates  on  gypsum ; 
while  the  effect  of  the  alkaline  silicates  on  porous 
lime  acts  favorably  for  the  hardening  of  the  silica 
molecule,  that  of  those  bodies  on  gypsum  is  quick. 


CEMENTS,  ETC. 


115 


almost  instantaneous,  which,  when  gypsum  is  brought 
in  contact  with  the  silica  sohition,  produces  a  raising 
or  effervescing,  giving  great  porosity  to  the  gypsum, 
which  scales  off  very  soon,  while  weak  silicate  solu- 
tions produce  more  satisfactory  results.  For  the 
purpose  of  possessing  good  results  in  plaster  w^orks 
it  is  proposed  an  intricate  mixture  of  80  parts  burnt 
and  pulverized  gypsum,  3  parts  slaked  lime,  10 
parts  powdered  silicate  in  sufficient  hot  w^ater.  All 
must  be  boiling. 

Cause  of  the  Hardening  of  Hydraulic  Cement. 

In  order  to  test  the  truth  of  the  different  hypothe- 
ses made  concerning  this  subject,  A.  Schulatschenke, 
seeing  the  impossibility  of  separating  from  a  mixture 
of  silicates  each  special  combination  thereof,  re- 
peated Fuch's  experiment,  by  separating  the  silica 
from  one  hundred  parts  of  pure  soluble  silicate  of 
potassa,  and,  after  mixing  it  with  fifty  parts  of  lime, 
placing  the  mass  under  water,  when  it  hardened 
rapidly.  A  similar  mixture  was  submitted  to  a  very 
high  temperature,  and  in  this  case  also  a  cement 
was  made.  As  a  third  experiment,  a  similar  mixture 
was  heated  till  it  was  fused;  after  having  been 
cooled  and  pulverized,  the  fused  mass  did  not  harden 
any  more  under  water.  Hence  it  follows  that  har- 
dening does  take  place  in  cement  made  by  the  wet 
as  well  as  the  dry  process,  and  that  the  so-called 


116 


HYDRAULIC  LIMESTONE, 


over-burned  cement  is  inactive,  in  consequence  of 
its  particles  having  suffered  a  physical  change. 

A  Strong  Cement  for  Iron. 

To  4-5  parts  clay,  dry  and  powdered,  2  parts 
iron  filings,  1  part  manganese,  -J  part  salt,  -J  part 
borax  in  a  paste  made  with  soluble  glass,  or  equal 
parts  zinc  white  and  manganese,  made  to  a  paste, 
must  be  used  immediately. 

The  Peasley  Cement. 

The  manufacturer  of  this  cement  has  made  him- 
self celebrated  and  wealthy  by  his  perambulations 
throughout  the  United  States  with  a  span  of  horses 
attached  to  a  load  of  hay,  so  it  is  thought  advisable 
to  enlighten  the  reader  with  its  composition  : 

White  glue,  dissolved  in  a  large  quantity  of  hot 
water,  also  50  parts  of  isinglass,  and  3  parts  of  gum- 
arabic,  and  3  parts  of  gum  traganth,  and  to  this 
solution  an  alcoholic  solution  of  white  shellac  ;  1  part 
of  the  latter  is  then  mixed  with  the  watery  solu- 
tion. To  the  wdiole  are  added  24  parts  of  white  lead 
and  12  parts  of  glycerine,  and  200  parts  of  alcohol. 
It  is  immediately  put  in  bottles  and  well  corked. 
In  other  words :  200  parts  white  glue,  24^  parts 
lead,  12  parts  glycerine,  200  parts  alcohol,  50  parts 
isinglass,  3  parts  gum  arable,  3  parts  gum  traganth, 
1  part  bleached  shellac. 


CEMENTS,  ETC. 


117 


The  Sir.TCATTON  of  Fresco  Painting. 

The  same  phenomena  attending  those  of  mortar 
take  place  in  fresco  painting.  It  is  known  that  the 
colors  prepared  by  water  on  the  rough  mortar  of  fat 
lime  and  sand  are  fixed  by  the.  carbonate  of  lime 
which  envelopes  them,  appearing  dull  in  many  re- 
spects, of  an  agreeable  appearance,  as  has  been 
demonstrated  in  the  durability  of  the  old  paintings 
of  Herculaneum  and  Pompeii,  which  have  been 
overthrown  by  rains  of  ashes  79  years  after  Christ, 
and  were  buried  in  a  depth  of  100  feet.  By  moist- 
ening with  the  liquid  silicates  the  walls  so  painted, 
the  surfaces  of  the  rough  mortar  of  fat  lime  assume 
the  properties  of  hydraulic  cement  and  acquire 
hardness. 

Silicate  Painting  by  Means  of  a  Brush. 

The  colors  rubbed  up  with  a  silicate  produce  an 
intimate  combination  of  the  carbonated  salts  and 
acids,  and  the  alkaline  of  the  silicates  are  separated 
thereby.  If  the  color  is  composed  of  a  material  un- 
susceptible for  a  chemical  affinity,  a  silicate  mass  is 
formed  by  the  action  of  the  atmospheric  carbonic 
acid,  which  makes  an  extraordinary  binding  cement, 
and  by  the  separation  of  the  alkali  assumes  a  perfect 
insolubility  in  a  very  short  time.  This  operation  is 
accelerated  if  a  coating  of  gypsum  has  been  laid  on  * 


118 


HYDRAULIC  LIMESTONE, 


the  lime,  and  becomes  more  solid  and  intimate, 
because  the  alkaline  and  silicate  acts  at  the  same 
time  on  the  coloring  and  carbonate  of  lime ;  in 
which  case  it  is  very  serviceable  to  moisten  the  wall 
before  applying  the  colors  with  a  weak  solution  of 
liquid  silica,  in  order  to  prevent  the  too  rapid  with- 
drawal of  the  silicate  and  cement  from  the  colors. 

Injection  of  Silicates. 

While  engaged  in  impregnating  the  soluble  sili- 
cates into  the  porous  stones,  and  carrying  this  opera- 
tion into  all  organic  and  inorganic  matter,  the  con- 
vincing proof  was  manifested  that  the  hardening  of 
those  bodies  are  only  owing  to  the  decomposition  of 
the  silicates,  effected  by  the  slow  action  of  the  atmos- 
pheric carbonic  acid  and  the  gradual  condensation 
of  silica.  This  phenomena  led  to  the  observations 
that  the  natural  silicates  and  aluminates,  as  well  as 
other  mineral  species,  were  similarly  formed  in  the 
moist  way. 

This  remarkable  reaction  of  hardening  porous 
bodies  by  silica  proves,  by  geological  observations, 
highly  probable  that  not  alone  all  the  enveloped  and 
crystallized  minerals  found  in  limestone  formations, 
but  also  an  endless  variety  of  silicated  and  all  urn  i- 
nated  substances  found  in  nature,  owe  their  exist- 
ence to  analagous  causes;  that  the  flints,  agates,  and 
*  petrifled  wood  cannot  have  any  other  origin,  but  that 


CEMENTS,  ETC. 


119 


they  are  formed  by  the  slow  decomposition  of  a  sili- 
cated  alkali  from  the  carbonic  acid,  either  atmos- 
pheric or  generated  during  the  process. 

This  fact  is  of  the  highest  interest  in  the  chemico- 
physical  investigations,  and  is  the  key  to  tlie  investi- 
gations of  the  formation  of  the  natural  silicates,  even 
under  many  various  circumstances,  of  the  conden- 
sation of  silica  by  other  bodies  than  the  carbonic 
.acid ;  many  experiments  undertaken  have  proved 
the  gradual  decomposition  as  already  stated,  and  in 
a  great  variety,  of  the  formation  of  such  as  opal, 
•quartz,  and  others  depending,  likewise  of  the  state 
of  concentration  of  the  original  decomposed  ma- 
terials. The  iridescence  of  the  opal,  which  disap- 
pears if  exposed  long  to  dry  atmosy)here,  but  revives 
if  moistened  in  water  or  sweet  oil,  gives  a  beautiful 
example.  Many  important  facts  have  come  to  light 
by  the  investigations  made  on  hydraulic  limes  and 
artificial  stones,  which  prove  that  a  considerable 
quantity  of  potash  is  contained  in  the  natural 
hydraulic  and  other  cements ;  the  origin  of  which 
is  attributed  to  the  decomposition  of  the  alkaline 
silicates  by  the  lime,  and  this  may  be  proved  by  the 
formation  of  saltpeter  or  nitrate  of  potash  in  the 
^fflorescenses  of  walls  and  earths  in  caves,  called  an 
-eremacausis  of  substances  which  contain  nitrogen, 
and  form,  therefore,  ammonia,  and  in  contact  with 
porous  substances  undergo  an  oxidation  and  conver- 


120 


HYDRAULIC  LIMESTONE, 


sion  into  nitric  acid,  and  at  once  is  combined  witli 
the  alkalies  contained  in  the  native  lime  occurring 
in  the  older  formations,  and  was  separated,  nndef 
certain  circumstances,  from  the  alkaline  silicates 
found  in  those  limestones,  nitrate  of  potash  the 
result.  In  general  terms,  nitre,  or  nitrate  of  potash, 
which  is  found  in  crusts  on  the  surface  of  the  earth, 
on  walls  and  rocks,  and  in  caves,  is  found  in 
there  localities  abundantly  in  certain  soils  of  Spain, 
Egypt,  Persia,  and  E.  In-dies,  especially  in  hot 
weather  succeeding  rains,  it  is  also  manufactured 
from  soils  where  other  nitrates  (nitrate  of  lime  or 
nitrate  of  soda)  form  in  a  similar  manner,  and  beds 
called  nitraries  are  arranged  for  this  purpose  in 
many  countries.  Refuse  animal  matter  also,  putri- 
fied  in  calcareous  soils,  gives  rise  to  nitrate  of  lime, 
as  w^e  find  it  so  frequently  in  cow  and  horse  stables, 
and  is  then  converted  into  nitrate  of  potash  ;  old 
plaster  walls,  when  lixiviated,  afford  about  5  ^  of 
nitre.  It  is  known  that  nitre  requires  for  its  forma- 
tion dry  air  and  long  periods  without  rain ;  the 
potash  comes  mainly  from  the  debris  of  felspathic 
and  lime  rocks  in  the  soil,  or  in  the  cements,  if  they 
have  been  used  for  building  walls,  and  the  oxidation 
of  the  nitrogen  of  the  air  is  promoted  by  organic 
matters,  hence  the  nitre  is  generally  associated  with 
azotized  decomposed  organic  substances.  A  nitre 
crust  from   the  vicinity  of  Constantine,  Algeria, 


CEMENTS,  ETC. 


121 


afforded  Boiissingault  S6%  nitrate  of  potash,  with 
some  nitrates  of  lime,  soda  and  magnesia.  In  the 
Mammoth  cave  of  Kentucky,  where  the  nitre  is 
found  scattered  throngh  the  loose  earth  in  great 
abundance,  and  was  utilized  during  the  war  of  1812, 
also  in  the  Mississippi  Yalley,  in  Missouri,  many 
caves  have  yielded  the  nitre  which  was  of  great  use 
to  the  secessionists  of  the  late  war,  when  Tennessee^ 
along  the  limestone  slopes  and  in  the  gorges  of  the 
Cumberland  table  hind,  produced  a  large  amount  of 
saltpeter. 

The  nitrate  of  soda,  formed  in  a  similar  manner 
like  that  of  nitrate  of  potash,  but  more  ])articiilarly 
found  in  the  dry  pampas  of  Chili,  where  it  is  found 
at  a  height  of  3,300  feet  above  the  sea,  and  contains 
beds  of  several  feet  in  thickness,  along  with  gypsum^ 
common  salt,  glauber  salt,  and  the  remains  of 'recent 
shells,  indicating  the  former  presence  of  the  sea. 

Kulilman  has  proved  by  his  investigations  that 
the  larger  number  of  limestones  from  various  geo- 
logical periods  contain  both  potash  and  soda,  deriving 
their  existence  from  various  plants  growing  in  a  cal- 
careous soil,  and  has  also  shown  the  development  of 
the  efflorescense  of  the  carbonates  of  potash,  chlor- 
ides of  potassium  and  sodiums,  which  make  their 
appearance  on  the  surface  of  walls  from  their  con- 
struction, to  which  he  was  led  by  the  fact  that  the 
alkaline  salts  in  general  are  obtained  in  larger  quan- 


122 


HYDRAULIC  LIMESTONE, 


titles  from  hydraulic  limes  than  from  the  lixiviation 
of  air  limes,  and  that  the  hydraulic  limes  contain 
mostly  more  alkali,  and  that  it  exerts  much  influ- 
ence upon  the  quality  of  lime,  and  it  has  been  ascer- 
tained by  Yicat  that  the  occurrence  of  the  potash 
and  soda  is  neither  accidental  nor  less  influential 
upon  the  proportion  of  the  hydraulic  limes.  It  is 
presumed  that  the  silicated  limestone,  and  any  fat 
lime  mixed  with  clay  by  the  influence  of  potash  or 
soda  are  during  the  burning  converted  into  double 
compounds*,  analagous  to  the  natural  silicates,  which 
are  known  under  the  name  of  zeolites,  such  as  meso- 
type,  stilbite,  apophyllite,  etc.,  which  all  form  hy- 
drates, and  lose  their  water  of  crystallization  by 
burning,  and  absorb  it  again  on  moistening ;  one  of 
the  species  of  that  class  of  mineral,  such  as  the 
laumonite  wliich,  when  exposed  for  some  time  to  the 
atmosphere,  eflloresces  and  crumbles  to  piec^  to  the 
chagrin  of  the  mineral  collectors,  but  it  is  suiiicient 
to  confirm  the  remark  just  made  regarding  their  con- 
stitution and  similarity  of  the  artiflcial  silicates  of 
lime  and  alumina.  It  is  apparent  that,  in  the  hard- 
ening of  hydraulic  lime  a  process  takes  place  anala- 
gous to  that  of  gypsum  when  hardening,  and  forming 
a  hydrate.  It  may,  however,  be  possible  that  the 
hydraulic  limes  be  still  formed  without  the  presence 
of  potash  or  soda,  and  that  the  silicium  or  aluminium 
in  contact  with  lime  fills  the  same  oflice  in  possessing 


CEMENTS.  ETC. 


123 


the  property  of  binding  the  water,  and  to  convert 
them  in  certain  conditions  to  a  hydrate.  Respect- 
ing the  cement  which  is  formed  by  the  moist  way, 
it  is  a  fact  that  when  chalk  is  brought  in  contact 
with  solutions  of  alkaline  silicates,  an  exchange  of 
the  acids  of  both  salts  takes  place,  one  part  of  the 
chalk  is  converted  into  silicate  of  lime  and  the  cor- 
corresponding  quantity  of  potash  in  carbonate  of 
potash  :  this  explains  the  true  artificial  stone  which 
has  become,  on  exposure  to  the  atmosphere  so 
hard,  that,  if  the  mixture  contains  a  sufficient  quan- 
tity of  a  silicate,  possesses  the  property  to  adhere 
firmly  to  such  bodies  where  it  has  been  applied,  the 
materials  so  formed  with  the  silicate  of  potash  or 
soda  are  analagous  to  cements  without  burning, 
and  may  be  used  for  restoring  monuments,  etc.  In 
the  sillification  of  artificial  stones  the  affinity  of 
lime  to .  the  silica  contained  in  the  soluble  glass  is 
manifest,  and  shows  the  effect  of  the  alkaline  sili- 
cates on  limestones;  and  how  the  influence  of  the 
atmosphere  in  the  hardening  of  silicates  or  artificial 
limes  is  brought  to  bear  through  the  atmospheric 
carbonic  acid  by  the  separation  of  one  part  of  silica 
in  the  silicates,  and  how  the  other  parts  of  the  sili- 
cate, when  in  close  contact  with  a  sufficient  quantity 
of  carbonate  of  lime,  a  lime  silicate  is  formed. 

This  acquired  knowledge  has  produced  numerous 
applications  in  industry,  it  has  proved  that,  by  arti- 


124 


HYDEAULIC  LIMESTONE, 


iicial  impregnation  of  mineral  substances  into  the 
interior  of  porous  substances  organic  as  well  as  inor- 
ganic matters  are  preserved,  or  silicified.  The  sili- 
fication  of  a  fine  sandstone  is  easily  effected  bj 
the  mixture  of  1  part  of  liquid  silica  and  2  parts  of 
fine  sand,  with  the  addition  of  a  small  quantity  of 
chalk  and  white  clay,  all  of  which  are  wrought  into 
a  paste  and  then  formed  into  desired  objects  and  ex- 
posed to  the  atmosphere  for  some  time,  and  the 
finishing  process  continued  by  means  of  hydraulic 
pressure  and  heating  in  hot  chambers,  the  particulars 
of  which  have  been  indicated  in  a  former  chapter. 
It  has  been  ascertained  that  always  if  any  salt  in- 
soluble in  water  is  brought  in  contact  with  the  solu- 
tion of  a  salt  which  forms  witli  the  acid  of  the  base 
of  the  insoluble  salt,  a  less  soluble  substance,  an 
exchange  takes  place,  which,  although  but  partial 
sometimes,  produces  the  formation  of  double  salts. 
This  discovery  led  to  a  direct  application  that  white 
lead,  chromate  of  lead,  chromate  of  lime,  and  the 
majority  of  the  carbonated  metallic  salts  are  suitable 
for  silicification. 


THE  SILICATE  PAINTING  ON  STONE, 

Stereo-Chromic. 

The  use  of  the  brush  in  the  application  of  colors- 
has  so  far  been  but  partially  accomplished.  The 
substitution  of  the  potash  or  soda  silicate  for  the 
fixed  and  volatile  oils  with  mineral  colors  has  at 
first  been  attempted  by  trituration  of  white  lead 
with  the  liquid  silicate.  It  has  been  found  that  a 
transformation  of  the  white  lead  takes  place  the 
moment  they  come  in  contact  together,  which  is  so 
rapid  that  no  time  is  allowed  to  transfer  the  paint 
into  the  brush.  In'  order  to  make  this  paint  more 
suitable,  and  to  prevent  a  kind  of  decomposition,  it 
was  found  advisable  to  add  a  large  portion  of  the 
sulphate  of  baryta,  artificially  prepared,  as  this  paint 
operates  but  slowly  on  the  silicate  solution. 

It  appears  that  this  baryta  may  be  used  with  more 
advantage  by  itself,  as  it  unites  perfectly  with  the 
silica  and  appears  to  form  a  chemical  compound,  but 
a  disadvantage  presents  itself  in  forming  but  a  half 
transparent  color,  which  does  not  cover  well,  and  the 
addition  of  oxide  of  zinc  is  therefore  recommended^ 
which  agrees  well  with  the  paint  in  connection  witb 
baryta  and  silica  ;  this  application  has  produced  very 


126 


SILICATE  PAINTING   ON  STONE. 


satisfactory  results,  forming  a  cheap  white  paint, 
which  can  be  easily  transferred  with  a  brush. 

Many  mineral  colors,  mixed  with  white  bases,  pro- 
duce such  difficulties  on  account  of  their  drying  too 
quick,  others  too  slowly,  according  to  the  behavior 
of  the  bases  to  the  soluble  glass.  Many  combina- 
tions retain  the  alkali  obstinately,  and  it  was  at- 
tended with  many  difficulties  to  apply  the  colors 
with  the  liquid  silica,  yellow  ochre,  bine  and  green 
ultramarine,,  sulphuret  of  cadium,  manganese  per- 
oxide the  oxide  of  chrome  have  proved  to  unite 
well  with  the  silica. 

The  painting  on  stone  is  much  easier  when  silica 
has  been  used  on  the  stone  than  on  that  where  it  was 
not  applied,  for  the  reason  that  the  absorbing  quality 
of  the  silica,  serving  a  binding. material,  withdraws 
it  from  the  color,  and  it  is  therefore  very  advisable 
to  apply  several  times  the  liquid  and  exposing  to  the 
atmosphere  before  applying  the  paint.  A  single  silifi- 
•cation  of  the  wall  is  indispensable  on  the  painted 
<3oloring,  which  is  done  by  preparing,  as  usual,  with 
the  liquid  silica,  as  other  paints  are  treated.  The 
«oda  silicate  used  for  painting  on  walls  is  easily 
-effected  by  the  use  of  the  syringe.  The  painting  on 
walls  is  attended  with  some  difficulty  likewise,  for 
w^hile  that  on  stone  remains  unaltered,  the  wood  is 
apt  to  shrink,  or  to  crack,  and  many  woods  will  not 
easily  take  the  paint,  and  even  change  their  physical 


SILICATE  PAINTING  ON  STONE. 


12Y 


appearance,  becomino;  darker  ;  oakwood  assumes  the 
appearance  of  an  old  wood,  and  only  the  white  and 
hard  woods,  such  as  the  ash  and  maple  woods,  will 
take  up  the  silicate  painting.  Another  difficulty 
takes  place  in  painting  on  wood,  that  it  peels  off,  if 
applied  too  thickly.  A  weak  solution  of  1  part 
silica,  of  28°  B  to  5  parts  water,  either  alone  or 
combined  with  other  bodies,  is  recommended. 

For  protecting  shingles  against  rot,  or  rendering 
them  incombustible,  4-5  applications,,  during  an 
interval  of  a  day  each,  may  be  made,  and  another 
method  is  to  season  them,  first  by  steam,  then  soak- 
ing them  in  green  vitriol  solution,  and  then  impreg- 
nating with  silica,  quite  hot,  and  at  last  to  throw 
fine  sifted  sand  upon  them.  Wooden  stables,  and 
other  buildings  exposed  to  vapors  or  great  change  of 
temperature,  three  or  four  coatings  of  the  silica  solu- 
tion is  recommended. 

Further  Remarus  on  Stereo-chromic. 

Tliis  new  art  of  painting  derives  its  name  from 
two  Greek  words  arepeoff^  fast,  or  permanent,  and 
from  jpcy/^^^j  the  color,  and  has  been  introduced 
as  a  substitute  for  fresco  painting,  and  bids  fair  to  be 
very  extensively  applied,  and  more  than  the  en- 
caustic painting,  from  the  fact  that  the  works  exe- 
cuted by  this  art  have  given  great  satisfaction ;  the 
inner  halls  of  the  new  museum  at  Berlin  have  been 


128 


SILICATE  PAINTING  ON  STONE, 


painted  by  Kaulbach  with  panels  21  feet  high  and 
24f  feet  broad,  and  are  said  to  equal  the  oil  paint- 
ings in  freshness  and  vigor,  and  with  that  particular 
advantage  that  the  paintings  may  be  viewed  or  ex- 
amined from  a  certain  stand  to  do  so,  and  that  it 
may  be  applied  on  many  grounds  without  the  rough 
mortar  being  first  used.  An  experiment  was  made 
to  expose  a  painting  for  one  year  to  the  atmospheric 
air,  to  the  sun,  fog,  snow  and  rains,  and  retaining 
during  the  whole  time  its  freshness.  An  important 
circumstance,  however,  is  the  formation  of  the 
groundwork,  for  any  neglect  in  that  of  the  lower 
and  upper  ground  materially  affects  the  beauty  of 
the  painting.  In  order  to  produce  a  uniform  strong 
firmness,  it  is  necessary  to  supply  the  soluble  glass 
uniformly,  so  that  it  ma}^  be  absorbed  perfectly  and 
uniformly. 

The  walls  must  be  well  cleansed  in  the  first  in^ 
stance  when  the  mortar  is  laid  on,  and  then  a  weak 
solution  of  the  liquid  glass  is  passed  over  it  and  left 
to  dry.  Clean  washed  sand  or  limey  sand  is  then 
mixed  with  a  very  small  quantity  of  burnt  lime,  and 
made  to  a  paste  and  laid  on  the  wall.  The  surface 
is  made  even  by  an  instrument,  and  the  upper  layer 
removed  which  was  formed  on  coming  in  contact 
with  the  air ;  but  the  mass  must  be  always  kept 
moist  during  the  whole  operation.  This  rough  mor- 
ter  will  soon  become  dry,  and  may  be  rubbed  off" 


SILICATE  PAINTING  ON  STONE. 


129 


with  the  fingers,  but  it  must  not  be  left  too  long  ex- 
posed to  the  air  for  fear  of  its  attracting  the  carbonic 
acid,  whereby  the  lime  would  be  too  much  carbon- 
ized. 

By  the  application  of  a  solution  of  carbonate  of 
ammonia  a  considerable  hard  consistency  is  produced, 
when  the  liquid  may  now  be  applied  several  times 
with  a  brush,  but  always  at  intervals,  and  enough 
to  penetrate  into  the  morter,  and  the  liquid  glass 
ought  to  be  that  made  from  soda,  and  quite  clear, 
that  liquid  soluble  glass  which  was  used  at  the 
Munich  Theatre  consisted  of  silica  23-21,  soda  8- 
20,  and  potash  2-52,  and  had  a  specific  gravity  of 
1,381,  and  was  then  diluted  by  an  equal  quantity  of 
water.  In  all  cases,  the  liquid  must  be  laid  on  by 
means  of  a  brush,  in  order  to  produce  a  uniform  im- 
pregnation of  the  same.  When  this  'groundwork, 
called  the  underground,  is  faithfully  and  carefully 
prepared,  the  upper  groundwork  which  is  to  receive 
the  painting  may  be  commenced  with ;  it  does  not 
ditfer  much  from  the  first  operation. 

The  sand  to  be  used  must  be  of  fine  grain,  and 
well  washed,  as  also  the  quartz,  etc.,  (tlie  lime  sand,) 
which  is  obtained  from  marble  or  dolomite,  finely 
powdered,  are  to  be  used  to  the  thickness  of  one 
line  quite  evenly,  in  order  to  obtain  the  necessary 
roughness  on  the  surface  indispensable  to  the  process 
of  painting.    It  may,  perhaps,  be  necessary  to  use 


130 


SILICATE  PAT^JTING  ON  STONE. 


other  substances  before  the  application  of  the  fine 
sand,  in  ord-er  to  destroy  any  lime  crust  which  might 
have  been  formed  in  the  preparation  of  underground, 
and  diluted  phosphoric  acid  is  now  recommended  to 
be  applied  with  a  sponge  or  brush  on  its  surface,  for 
it  forms  then  a  phosphate  of  lime  with  the  soluble 
glass,  which  binds  well  and  does  not  injure  the 
mortar.  The  ground  so  prepared,  and  well  dried,  is 
now  impregnated  with  the  liquid  glass,  the  same  as. 
the  first,  and  diluted  also  with  equal  quantities  of 
water,  which  is  done  twice,  allowing  sufiicient  time 
to  dry  between  each  impregnation. 

VYood  may  be  painted  by  covering  it  first  with  a 
chalk  ground,  which  must  be  thick  enough  to  allow 
a  polishing  with  pumice  :  to  chalk,  glue,  or  a  little 
silicate  solution  may  be  added,  as  a  binding  material. 
•Another  difficulty  occurs  after  the  first  has  been 
overcome,  in  the  oozing  out  of  the  carbonate  of 
potash  in  damp  weather  until  the  whole  salt  has 
been  expelled,  and  many  experiments  have  failed, 
and  hydrochlorate  of  ammonia  was  first  proposed  in 
a  weak  solution,  and  an  absolute  insolubility  of  the 
<3olor  was  thereby  obtained,  but  chlorate  of  potash 
remained  in  this  operation,  which  destroys  the  gloss 
of  the  colors  if  not  at  once  removed  by  repeated 
washing ;  forced  to  resort  to  those  few  chemical 
agents,  apt  to  fix  the  potash,  which  should  enter  as 
insoluble  combinations  in  the  color  without  destroy- 


SILICATE  PAINTING  ON  STONE. 


131 


iiig  them  ;  the  perchloric  and  hydrofluoric  acids  were 
resorted  to.  It  is  well  known  that  by  washing  with 
hydrofluoric  acid  the  density  of  the  colors  is  much 
increased,  and  it  was  thought  therefore  sale  to  use  it^ 
particularly  in  painting  on  glass,  but  only  as  a  very 
weak  solution.  Hydrofluoric  acid  possesses  the  most 
remarkable  property  to  dissolve  most  oxides  when  in 
a  concentrated  state.  The  application  of  the  weak 
solution  of  hydrofluoric  acid,  either  for  fixing  the 
potash  in  painting  and  in  siliflcation  of  limestone^ 
was  mainly  calculated  for  such  case  where  a  silicate 
has  been  used  with  an  excess  of  potash,  and  in  hard- 
ening of  soft  and  porous  limestones  by  a  partial  con- 
version into  a  lime  silicate  it  was  found  very  expe- 
dient for  fixing  the  potash,  and  making  sure  the  in-^ 
solubility  to  moisten,  at  first  with  a  weak,  and  then 
strong  solution  of  the  hydrofluoric  acid,  the  stones* 
when  the  potash  oozed  out;  the  acid,  however,  pene- 
trated the  stone  and  produces  an  insoluble  com- 
pound, in  other  words,  it  fixes  the  soluble  potash, 
and  produces  an  insoluble  compound.  Through  thia 
discovery  hydrofluoric  acid  was  found  a  very  useful 
application  in  the  fluosilicated  lime. 

If  brought  in  contact  with  lime,  hydrofluoric  acid 
is  capable  of  dissolving  it  considerably  without  pro- 
ducing an  immediate  precipitate  of  calcium,  or  a 
separation  of  the  silica,  but  at  a  certain  state  of  satu- 
ration any  addition  of  lime  decomposes  entirely  the 


132  8ILICATE  PAINTING  ON  STONE. 

bydrofluoric  acid,  and  so  miicli  that  not  a  trace 
of  these  bodies  can  be  discovered  in  the  fluid  ;  the 
same  results  are  obtained  by  the  carbonate  of  lime, 
instead  of  the  caustic  lime,  and  that  silicium  and 
fluor  are  produced  in  the  limestone,  which  hardens 
l)ut  slowly,  and  it  is  therefore  simply  a  fluorsilication 
that  produces  the  hardening  of  the  lime.  The  effect 
of  the  hydrofluoric  acid  on  gypsum  is  also  produced 
in  a  cold  mixing  of  both,  when  the  surface  of  the 
gypsum  is  considerably  hardened.  If,  however,  the 
acid  is  used  in  excess,  the  gypsum  is  covered  with 
raised  postules,  which  owe  their  existence  to  the  for- 
mation of  bisulphate  of  lime,  because  sulphuric  acid 
•does  not  act  as  well  as  the  carbonic  acid  in  the 
treatment  of  limestone;  a  fluorcalcium,  mixed  with 
soluble  glass,  may  be  used  as  a  paint,  or  paste,  or  a 
•  cement,  or  any  coating  of  other  substances,  and  be- 
comes so  hard  and  weatherproof  that  neither  soda 
nor  potash  will  detach  from  the  combination  and 
remain  dry. 

Painting  on  Metals,  Glass  and  Porcelain. 

Silica  painting  adheres  strongly  on  metals,  pro- 
vided care  is  taken  to  keep  the  substances  some  time 
from  the  contact  with  water.  The  most  durable 
paint  is  produced  on  zinc,  also  on  porcelain  and 
glass,  the  colors  assume  a  semi-transparency  if 
painted  on  glass,  and  no  doubt  afl'ord  much  induce- 


SILICATE    PAINTING    ON  STONE. 


133 


iiient  for  its  use.  -  The  sulphate  of  baryta,  aTtificially 
prepared,  combined  with  potash  silicate,  appled  to 
glass,  makes  a  milky  white  appearance,  and  is  very 
beautiful,  as  it  incorporates  very  intimately  with  the 
silica,  so  that  after  the  lapse  of  .a  few  days  the  paint 
cannot  be  removed  even  with  warm  water.  If  this 
glass  is  exposed  to  high  heat  (6°  Wedgewood)  a  fine 
white  enamel  is  formed  on  the  surface,  which  will 
compare  well  with  the  oxyde  of  tin,  and  is  much 
cheaper.  Ultramarine,  oxide  of  chrome,  if  con- 
verted into  enamels,  form  a  prolific  source  for  the 
new  art  of  painting.  It  is  not  quite  necessary  that 
a  cliemical  combination  should  be  produced  in  all 
these  colors,  if  they  only  adhere  strongly  and  pro- 
duce the  silicated  cement  which  has  become  hard  by 
its  fine  division  and  easy  admission  of  air. 

Emery,  bloodstone,  and  peroxide  of  manganese,  if 
finely  powdered  and  prepared  with  a  concentrated 
solution  of  soluble  glass,  produce  cements  of  extra- 
ordinary hardness,  resisting  the  effect  of  heat  com- 
pletely, and  become  perfectly  insoluble  in  water. 

For  the  production  of  an  indestructible  ink,  soluble 
glass  has  been  used  and  obtained  by  mixing  finely 
burnt  lampblack  with  the  liquid  soluble  glass.  Bra- 
connofs  hik  is  prepared  by  decomposing  leather  in 
caustic  potash  and  adding  to  the  black  mass  the 
liquid  soluble  glass.  A  decoction  of.  cochineal 
mixed  with  the  liquid  soluble  glass  produces  a  red 

6 


134 


SILICATE  PAINTING  ON  STONE. 


ink,  resisting  completely  the  action  of  chlorine  and 
all  other  acids. 

The  alkaline  salts,  particularly  the  carbonates  and 
chlorides,  produce,  when  added  to  liquid  silica,  a 
gelatinous  pasty  precipitate,  the  chloride  of  am- 
monium with  developing  the  ammonia;  precipitates 
are  also  formed  with  the  earthy  alkaline  salts,  and 
from  alumina  and  hydrate  of  lime,  for  in  all  these 
cases  of  precipitations  a  part  of  potash  is  withdrawn 
from  the  soluble  glass,  which  either  forms  a  part  of 
the  precipitate  or  remains  free,  or  attaches  itself  to 
the  acid  of  the  added  salt. 

The  same  case  takes  place  in  the  application  of 
the  salts  of  the  heavy  metals,  such  as  iron,  copper, 
etc.  The  effect  of  tlie  soluble  glass  on  salts,  either 
insoluble  or  soluble  with  difficulty  in  water,  such  as 
sulphate  of  potash  and  carbonate  of  lead,  phosphate 
of  alumina,  gypsum,  etc.,  all  of  which  become,  when 
rubbed  up  with  the  silica  solution  and  exposed  to 
the  air,  a  very  hard  mass. 

The  fixation  of  potash  with  silica  painting  on  lime 
shows  how  the  colors,  after  an  exposure  to  air  for 
some  time,  become  quite  insoluble  in  water,  and  is 
thus  explained  :  The  contact  of  carbonate  of  lime 
with  the  soluble  glass  determines  always  the  decom- 
position of  the  first,  and  conversion  in  silicate  of 
lime,  which  retains  the  coloring  matter.  If  the 
colors  are  transferred  on  substances  not  acting  upon 


SILICATE  PAINTING  ON  STONE. 


135 


the  soluble  silicates  like  wood,  iron,  glass,  etc.,  then 
it  becomes  necessary  to  find  the  conditions  of  the 
insolubility  in  the  reaction  of  the  coloring  matter  in 
the  silicate  itself. 

Much  precaution  has  to  be  used  not  to  close  the 
pores  of  the  underground,  whereby  the  success  of 
the  painting  is  jeopardised,  in  case  a  mistake  should 
have  occurred  before,  and  by  waiting  some  time  be- 
fore proceeding  farther,  to  allow  the  contraction  of 
the  liquid  glass,  so  as  -to  open  again  the  pores,  and 
which  can  also  be  accelerated  by  heat  that  is  pro- 
duced by  burning  alcohol  over  the  groundwork. 
Now,  after  this  operation  of  drying  and  prei>aring 
is  performed,  and  the  liquid  glass  applied  uniformly, 
so  that  every  paint  is  found  uniform  so  as  to  begin 
the  painting,  the  artist  will  have  no  difficulty  to 
begin  at  the  proper  work.  The  colors  are  now  per- 
fectly rubbed  up  with  the  water  and  put  on  artisti- 
cally after  the  wall  has  been  syringed  with  pure 
water — for  two  reasons :  one  is  to  expel  the  air  from 
the  pores,  and  then  to  promote  the  adhesion  of  the 
colors ;  this,  however,  must  be  done  moderately,  or 
the  colors  might  otherwise  suffer  in  freshness  ;  the 
moistening  must  be  effected  on  every  spot  which  has 
to  be  painted.  The  colors  are  now  prepared  with 
the  liquid  glass,  diluted  with  one-half  of  its  water, 
which  must  be  applied  by  means  of  a  syringe,  and 
not  by  a  brush,  and  with  much  care,  for  the  reason 


136  SILICATE  PAINTING  ON  STONE. 

that  these  colors  adhere  but  thinly,  and,  if  applied 
with  the  least  force,  would  put  the  colors  from  their 
place,  or  would  make  them  flow  together ;  the  opera- 
tion of  syringing  over,  the  painting  must  be  repeated 
several  times  after  having  become  dry,  until  the 
colors  appear  to  be  so  fast  that,  touching  with  the 
fingers,  they  will  not  be  stained.  Many  colors  re- 
quire more  or  less  of  the  liquid  glass,  which  may  be 
learnt  by  practice,  but  which  may  easily  be  detected. 

When  the  painting  is  finished,  an  application  of 
alcohol,  after  the  lapse  of  a  few  days,  will  materially 
add  to  fasten  the  painting  and  to  clear  it  from  any 
impurities  which  may  have  atta(;hed  themselves,  or 
by  the  alkali  which  might  have  been  separated  from 
the  liquid  glass  and  have  oozed  out,  and  may  be 
worked  with  mortar  free  from  lime,  and  it  may  thus, 
without  any  hesitation,  be  left  exposed. 

It  may  be  observed  that  the  painting  must  be 
guarded  against  rains  during  the  time  of  the  rub- 
bing up  and  laying  on  of  the  colors.  After  the  ex- 
posure of  some  months,  or  a  year  at  latest,  it  is 
well  to  examine  the  painting,  in  order  to  ascertain 
whether  the  colors  have  not  suffered  from  rhe  con- 
densation of  the^  liquid  glass,  so  as  to  produce  an 
interruption  of  the  binding  or  fastening  of  the  colors, 
so  that  it  may  become  necessary  to  apply  an  ad- 
ditional fixation. 

The  materials  for  the  upper  ground,  which  is  to 


SILICATE  PAINTING  ON  STONE. 


137 


take  up  the  colors,  may  be  also  composed  of  the  fol- 
lowing: Pulverized  marble,  dolomite,  slaked  lime, 
and  fine  quartz,  or  a  sand  with  the  liquid  glass  com- 
bined; the  proportion  of  the  liquid  glass  depends 
upon  the  sand  which  is  used  in  the  mixture,  so  as  to 
form  the  consistency  of  mortar.  The  advantages  of 
this  ground  work  are :  it  prevents  the  separation  of 
the  lime  on  the  surface  after  a  frequent  moistening 
with  water,  and,  therefore,  no  lime  crust  forming,  no 
rubbing  off  is  required  before  the  application  of  the 
liquid  glass;  furthermore,  the  liquid  glass  comes  in 
immediate  contact  with  the  under  ground,  producing 
thereby  a  good  cement  with  both  grounds.  This 
mortar  becomes  as  liard  as  stone  after  being  dry, 
and  shows  its  porosity  in  warm  and  dry  air,  which 
make  it  very  susceptible  for  absorption. 


Stereocuromic  for  Easel  Painting. 

The  basis  for  this  class  of  painting  may  be  made 
from  plates  of  burnt,  porous  clay  ;  it  is  first  im- 
pregnated sufficiently  with  liquid  soda  glass.  These 
plates  may  be  f  of  an  inch  thick  ;  after  one  or  two 
applications  they  become  as  hard  as  any  stone  ware ; 
they  are  very  suitable  for  painting  ground.  The 
lithographic  stone  makes  a  good  base  for  easel  paint- 
ing ;  a  thin  coating  of  liquid  glass  mortar  will  pro- 
duce a  good  base,  and  it  may  be  first  moistened  with 


138 


SILICATE  PAINTING  ON  STONE. 


phosphoric  acid,  which  assists  much  to  absorb  the 
colors  with  the  liquid  glass  and  to  make  them  fast. 

The  colors  to  be  used  for  this  class  of  painting 
ought  hot  to  be  chosen  which  decomposes  the  liquid 
glass,  such  as  contain  strong  acids,  nor  those  from 
organic  substances.  Burnt  oxides  are  better  than 
raw  oxides,  vermillion  becomes  brown,  and  at  last 
black  ;  cobalt  blue  becomes  clearer  by  the  liquid, 
and  the  yellow  ochre  becomes  darker. 

All  colors  ought  to  be  properly  prepared  to  make 
them  fit  for  the  silica  painting,  such  as  the  great 
variety  of  oxides,  many  of  which,  not  containing 
much  oxide  of  iron,  may  be  suitable,  also  chrome  red, 
ultramarine,  umber,  baryta  white,  cadmium  yellow, 
and  many  more,  purposely  made  by  some  chemists, 
not  containing  free  acid,  which  enter  into  a  decom- 
posing chemical  combination. 

The  permanent  white,  or  artificial  sulphate  of 
baryta,  is  said  to  be  the  proper  material  for  a  white 
paint.  It  is  obtained  from  the  native  minerals, 
heavy  spar  or  sulphate  of  baryta,  and  witherite  or 
carbonate  of  baryta.  The  manufacture  of  the  new 
paint  is  efi*ected  by  the  reduction  of  the  native  sul- 
phate to  a  chloride  of  barium,  or  dissolving  the 
native  witherite  in  hydrochloric  acid,  and  then  ad- 
ding either  sulphuric  acid  or  glaubersalt,  the  arti- 
ficial sulphate  of  baryta  is  found  in  a  condition  of 
extreme  fineness  and  purity,  possessing  a  fine  lustre. 


SILICATE  PAINTING  ON  STONE. 


139 


and  suscsptible  for  producing  a  fine  white  paint, 
which  is  the  b3st  substitute  for  white  lead  and  zinc 
white,  is  not  subject  to  tarnish  or  become  brown  in 
parlors  like  white  lead,  which  is  attacked  by  hydro- 
sulphuric  acid,  and  forms,  when  combined  with  the 
liquid  glass,  a  slow  but  intimate  combination,  and  is 
likewise  used  under  the  name  of  blanctix  for  card- 
makers,  paper-stainers  and  paper  collar  manufacturers 
to  a  very  large  extent.  It  may  also  be  considered  in 
point  Of  importance^  if  compared  with  that  of 
white  lead,  not  having  a  dilatory  effect  upon  health 
as  the  latter.  If  mixed  with  the  soluble  glass  it  obvi- 
ates the  odious  smell  of  linseed  oil  and  spirits  of  tur- 
pentine. If  it  is  mixed  with  dexterine,  starch,  or  other 
binding  material  in  connection  with  the  liquid  sili- 
cate of  soda,  its  applications  may  be  multiplied  to 
any  extent. 

The  artificial  sulphate  of  baryta  is  largely  manu- 
factured on  the  continent  of  Europe ;  in  the  U.  S.  it 
has  so  far  bean  manufactured  in  New  York  by  a  few 
chemical  establishments  for  card  makers,  but  not  yet 
for  the  purpose  of  substituting  it  to  white  lead. 


SILIFICATION  OF  WOOD 


A  Protection  against  Combustion,  Inflammabil- 
ity AND  Dry  Rot. 

Wood,  and  all  other  organic  combustible  substances, 
may  to  a  great  extent  be  preserved  against  that  great 
element,  the  fire,  by  the  proper  application  of  the 
liquid  silicates.  Still  it  requires  much  skill,  expe- 
rience, and  proper  management  to  subdue  totally 
this  wonderful  element  when  brought  to  its  full 
power.  There  are  many  instances  on  record  to  prove 
either  a  full,  or  at  least  partial  success  in  arresting 
the  progress  of  a  conflagration  by  the  impregnation 
or  coating  of  combustible  bodies  with  many  sub- 
stances, such  as  possess  incombustibility,  whether 
liquids,  gases,  or  materials  which  possess  the  proper- 
ties of  generating  gases  that  will  withdraw  or  sufib- 
cate  the  surrounding  atmosphere,  such  as  the  oxygen 
gas,  and  thereby  arrest  the  progress  of  the  flames. 
Many  chemical  agents  have  been  from  time  to  time 
proposed  to  effect  this  object ;  such  as  salt,  chloride 
of  lime,  and  latterly  carbonic  acid  in  its  gaseous 
form,  and  many  metallic  salts  have  proved  but  a  par- 


SILIFICATION  OF  WOOD. 


141 


tial  success  in  the  prevention  of  decay  or  dry  rot  of 
wood.  The  soluble  glass  is  one  of  the  first  materials 
which  have  been  successfully  employed  in  arresting 
conflagration,  and  as  far  as  1823.  this  material  w^as 
recommended  in  the  construction  of  the  Munich 
Theatre,  where  465,000  square  feet  of  timber  surface 
were  treated  with  a  coating  of  the  liquid  soluble 
glass,  and  in  1830,-31  and  '32  the  author  performed 
many  experiments  in  the  Brooklyn  Navy  Yard,  par- 
tially as  a  protecting  agent  against  fire,  as  also 
against  decay  of  the  w^oody  fibre ;  small  square 
blocks  of  wood,  after  having  been  impregnated  with 
the  soluble  glass  and  sailcloth,  writing  paper,  parch- 
ment, etc.,  were  exposed  for  some  time  to  the  flame 
of  a  gas  lam]).  After  the  lapse  of  an  liour,  all  these 
substances  were  found  to  be  charred,  but  not  con- 
sumed. It  is  proved  that  the  liquid  soluble  glass 
produces  a  perfect  adhering,  permanent  covering 
which,  when  properly  laid  on,  suflers  no  damage 
from  the  atmosphere.  For  coating  the  wood,  etc.,  a 
pure  solution  of  tlie  liquid  glass  is  required,  other- 
wise it  will  peel  ofl',  and  it  is  best  not  to  use  it  first 
in  a  concentrated  state,  as  it  will  not  be  able  to  pene- 
trate into  the  pores,  whereby  the  atmosphere  must 
be  expelled,  and  even  five  or  six  applications  may  be 
made  in  intervals  of  twenty  four  hours.  Although  this 
process  renders  good  services,  it  may  be  improved  by 
the  addition  of  other  pulverized  substances,  wherein 


142 


SILTFICATION  OF  WOOD. 


the  soluble  glass  acts  as  the  binding  material,  the  coat- 
ing assumes  a  better  body,  is  stronger  and  more  per- 
manent, and  if  exposed  to  the  fire  a  crust  is  formed 
such,  for  instance,  are  bone  dust,  clay  and  chalk 
mixed  together,  a  lead  glass,  etc.  ;  common  clay 
was  successfully  used  with  the  liquid  glass  in  the 
Munich  Theatre.  If  applied  on  linen  or  other 
organic  textures,  the  mere  coating,  or  dipping,  is  not 
sufficient,  but  a  surface  between  rollers  must  be  re- 
sorted to  in  order  to  produce  a  full  absorption  with 
the  pores ;  these  stuffs  may  then  be  rolled  up,  but 
not  folded. 

Building  timber,  rail  road  sleepers,  and  other  sim- 
ilar materials,  have  been  treated  in  the  manner  just 
described,. and  were  protected  fully  against  fire  and 
dry  rot. 

The  author  proposed  a  combination  of  the  liquid 
glass  with  the  following  substances,  intended  as  de- 
composing agents  by  chemical  affinity,  and  pro- 
ducing in  the  cells  of  the  vegetable  fibre  the  various 
mineral  and  metallic  salts  which  are  altogether  in- 
soluble in  water,  alkalies  and  acids,  and  he  extended 
his  experiments  on  the  uses  of  lime,  chalk,  gypsum, 
copperas,  etc.  His  process  of  treating  ship  timber, 
sleepers,  cross-ties,  roofing  shingles,  and  other  wood 
blocks  was  the  following  : 

1.  The  materials  to  be  treated  were  put  in  steam- 
boilers  and  exposed  for  four  hours  to  a  pressure  of 


SILIFICATION  OF  WOOD. 


143 


hot  steam,  (or  300*^  F)  then  withdrawn  from  the  ket- 
tles and  dried.  Alkalies  and  acids,  such  as  hydro- 
chloric, have  been  since  recommended  for  the  purpose 
of  abstracting  color  and  albumen  existing  in  the  cells 
of  the  woody  fibres,  which,  however,  is  accomplished 
by  steaming. 

2.  In  a  solution  of  silicate  of  soda  while  hot,  the 
materials  to  be  treated  are  thrown  and  kept  there  for 
twenty-four  hours,  which  will  give  ample  time  for 
the  woods  to  enter  into  the  open  cells  while  hot. 

3.  A  large  vat,  containing  either  lime  water,  solu- 
tion of  copperas,  or  blue  vitriol,  white  vitriol  or 
gypsum,  finely  powdered  and  thrown  into  hot  water, 
or  finely  powdered  chalk  of  1  ft),  to  10  gallons  of 
water:  the  proportion  of  metallic  salts  is  but  J  fb. 
to  the  gallon  of  water.  The  woods  are  kept  in  the 
vats  for  another  day,  and  then  taken  out  dried  and 
ready  for  use. 

Coal  tar,  and  the  other  products  of  dry  distilla- 
tion from  tar  and  peat,  have  been  recommended  by 
Krieg  as  far  back  as  1858,  under  the  name  of  Kreo- 
sote-carbolic  acid,  which  was  then  considered  a 
waste  product,  and  in  its  raw  state  having  a  spec, 
grav.  of  1.02  to  1.058,  and  yielded  from  20  to  30  % 
of  the  tar,  it  was  well  known  to  possess  the  property 
of  protecting  wood  against  decay. 

This  chemist  combined  with  the  impregnation  of 
woods,  etc.,  the  soluble  glass  that  of  the  kreosote  car- 


144 


SILIFICATION  OF  WOOD. 


bolic  acid  for  the  reason  that  the  latter  precipitates 
the  soluble  silica  as  an  insoluble  substance  while  it  is 
soluble  in  an  alkaline  Ije.    He  proposed  to  expose 
the  woods  for  f  of  an  hour  to  a  temperature  of  300°  p 
F.,  and  then  drying  them  thoroughly. 

The  woods  thus  prepared  showed  an  increased 
weight  of  6  and  a  lacquered  surface,  while  in  the 
inside  the  pores  were  filled  with  an  insoluble  precipi- 
tated silica. 

For  effecting  a  still  more  perfect  success  is  to  fix 
the  kreosot  on  the  woody  fibre  from  the  alkaline  so- 
lution, by  the  diluted  sulphuric  acid  or  by  a  solution 
of  copperas  (sulphate  of  iron,)  whereby  the  sulphate  of 
soda  thus  obtained  may  either  be  washed  out,  or  oozed 
out,  and  the  creosot-carbolic  acid  combines  stronger 
with  the  woody  fibre,  and  the  impregnated  woods 
may  be  considered  safely  protected  against  fire  or 
rot. 

This  process  just  described,  deserves  the  serious 
attention  of  the  various  companies  established  for 
the  last  five  years  in  the  preservation  of  wood  by 
carbolic  acid,  tar,  etc.,  by  combining  the  soluble 
glass  with  their  process,  as  we  have  described. 

Since  the  introduction  of  railroads,  not  quite  60 
years,  many  men  have  been  engaged  in  chemical 
experiments  upon  the  cross  ties  and  sleepers,  which 
after  being  laid  dawn  for  a  few  years  undergo  the 
decay  or  rot  and  have  to  be  renewed,  which  causes 


SILIFICATION  OF  WOOD. 


145 


great  expenses  to  the  companies.  Kyan,  Burnett, 
Boucherie  and  many  other  chemists  in  all  .coun- 
tries where  this  evil  existed,  proposed  remedies ; 
the  sublimate,  chloride  of  zinc,  pyrolignite  of  iron, 
all  had  their  advantages  and  disadvantages;  of 
late  borax,  alum,  rosin,  carbolic  acid  have  been  in- 
troduced and  many  articles  have  been  written  on 
the  subject. 

Preservation  of  Wood,  in  Damp  and  Wet  Places. 

In  1846,  80,000  sleepers  of  the  most  perishable 
woods,  impregnated,  by  Boucherie's  process,  with 
sulphate  of  copper,  were  laid  down  on  French  rail- 
ways :  after  nine  years  exposure,  they  were  found  as 
perfect  as  when  laid.  We  would  suggest  washing 
out  the  sap  with  water,  which  would  not  coagulate 
its  albumen  :  the  solution  would  appropriately  fol- 
low. Both  of  the  last  named  processes  are  compara- 
tively cheap ;  it  costs  less  than  creosoting,  but  one 
shilling  per  sleeper.  The  unpleasant  odor  of  creosote 
is  greatly  against  its  use  for  lumber  for  dwellings ; 
pyrolignite  of  iron  is  offensive,  and  also  highly  in- 
flammable; the  affinity  of  the  chlorides  for  water 
keeps  the  structure  into  which  they  are  introduced, 
wet,  and  they  also  corrode  the  iron-work.  Sulphate 
of  copper  is  free  from  these  objections,  and  is  cheaper 
than  the  chlorides,  and  seems  preferable  for  protect- 
ing wooden  structures  against  dry  rot  in  damp  situa- 


146 


SILIFICATION   OF  WOOD. 


tions,  like  mines,  vaults,  and  the  basements  of  build- 
ings. 

The  surface  of  all  timber  exposed  to  alternations  of 
wetness  and  dryness  gradually  wastes  away,  becoming 
dark  colored  or  black.  This  is  really  a  slow  combus- 
tion, but  is  commonly  called  wet  rot,  or  simply  rot. 
Other  conditions  being  the  same,  the  most  dense  and 
resinous  woods  longest  resist  decomposition.  Hence 
the  superior  durability  of  the  heart  wood,  in  which 
the  pores  have  been  partly  filled  with  lignin,  over 
open  sap  wood  ;  and  of  dense  oak  and  lignum  vitae  over 
light  popular  and  willow.  Density  and  resinousness 
exclude  water ;  therefore  our  preservatives  should  in- 
crease those  qualities  in  the  timber.  Fixed  oils  fill  up 
the  pores  and  increase  the  density  ;  the  essential  oils 
resinify,  and  furnish  an  impermeable  coating ;  but 
pitch  or  dead  oil  possesses  advantages  over  all  known 
substances  for  the  protection  of  wood  against  changes 
of  humidity.  According  to  Professor  Lethehy 
("  Civil  Engineers'  Journal,"  vol.  33),  dead  oil,  1st, 
coagulates  albuminous  substances;  2d,  absorbs  and 
appropriates  the  oxygen  in  the  pores,  and  so  protects 
from  eremacausis ;  3d,  resinifies  in  the  pores  of  the 
wood,  and  thus  shuts  out  both  air  and  moisture ;  and 
4th,  acts  as  a  poison  to  lower  forms  of  animal  and 
vegetable  life,  and  so  protects  the  wood  from  all  para- 
sities.  These  properties  specially  fit  it  for  impregnat- 
ing timber  exposed  to  alternations  of  wet  and  dry 


SILIFICATION  OF  WOOD. 


147 


states,  as,  indeed,  some  of  them  do  for  situations  con- 
stantly damp  and  wet.  Dead  oil  is  distilled  from  coal 
tar,  of  which  it  constitutes  about  30  ^  cent,  and  boils 
between  300^  to  470°  Fahr.  Its  antiseptic  quality  re- 
sides in  the  creosote  it  contains.  One  of  the  compon- 
ents of  the  latter,  carbolic  acid,  (phenic  acid,  phenol) 
Q12  Q2^  ^Yie  most  powerful  antiseptic  known,  is  able 
at  once  to  arrest  the  decay  of  every  kind  of  organic 
matter.  Professor  Letheby  estimates  this  acid  at  one 
half  to  six  per  cent,  of  the  oil.  Bethell's  process  sub- 
jects the  timber  and  dead  oil,  enclosed  in  large  iron 
tanks,  to  a  pressure  varying  from  one  hundred  to  two 
hundred  pounds  per  square  inch,  about  twelve  hours : 
from  eight  to  twelve  pounds  of  oil  are  thus  injected 
into  each  cubic  foot  of  wood.  Lumber  thus  prepared 
is  not  attected  by  exposure  to  air  and  water,  and  re- 
quires no  painting.  Four  pence  the  cubic  foot  is 
estimated  as  the  probable  expense  of  this  process. 

Though  we  have  not  to  guard  against  decay,  when 
timber  is  constantly  wet  in  salt  water,  the  Toredo- 
navalis^  a  mollusk  of  the  family  Tuhicolaria  (Lam.) 
soon  reduces  to  ruin  any  unprotected  submarine  con- 
struction of  common  woods.  Kone  of  our  native 
timbers  are  exempt  from  these  inroads.  The  toledo 
never  perforates  below  the  surface  of  the  sea-bottom, 
and  probably  does  this  little  injury  below  low-water 
mark  ;  its  food  is  the  borings  of  the  wood.  Poisoning 
the  timber  does  not  protect  from  the  toledo,  the  con- 


148 


SILIFICATION  OF  WOOD. 


stant  motion  of  sea-water  soon  diluting  and  washing 
away  the  small  quantity  of  soluble  poison  with  which 
the  wood  has  been  injeted.  Thorough  creosoting 
the  wood,  with  ten  pounds  of  dead  oil  per  cubic  foot, 
is  a  complete  protection  against  the  toledo. 

Drying  Timber  by  Steam. 

Mr.  Yiolitter  has  lately  presented  to  the  Academy 
of  Sciences  in  Paris,  a  very  able  communication  on 
the  desiccation  or  drying  of  different  kinds  of  wood 
by  steam.  He  states  that  steam  raised  to  482°,  Fah- 
renheit, is  capable  of  taking  up  a  considerable  quan- 
tity of  water ;  and  acting  upon  this  knowledge,  he 
submitted  difierent  kinds  of  oak,  elm,  pine,  and  wal- 
nut, about  eight  inches  long  and  half  an  inch  square, 
to  a  current  of  steam  at  seven  and  a  half  pounds  pres- 
sure to  the  square  inch,  but  which  was  afterwards 
raised  to  482^.  The  wood  was  exposed  thus  for  two 
hours.  It  was  weighed  before  it  was  exposed  to  the 
steam,  and  afterward  put  into  close-stoppered  bottles 
until  cool,  when  the  samples  were  again  weighed, 
and  showed  a  considerable  loss  of  weight,  the  loss  of 
which  increased  with  the  increase  of  the  temperature 
of  the  steam.  For  elm  and  oak  the  decrease  in  weight 
was  one-half,  ash  and  walnut  two-fifths,  and  pine 
one-third.  The  woods  underwent  a  change  of  color 
as  the  heat  was  rising  from  395*^  to  442'^ ;  the  walnut 
became  very  dark,  showing  a  kind  of  tar  formed  in 


SILIFICATION  OF  WOOD. 


149 


the  wood- by  the  process,  which  was  found  to  have  a 
preserving  effect  on  the  wood. 

It  was  found  that  wood  thus  heated  became  stronger, 
having  an  increase  in  the  power  of  resisting  fracture. 
The  maximum  heat  for  producing  the  best  fracture- 
resisting  power  for  elm  was  between  302  and  34Y^, 
and  between  257  and  303  degrees  for  the  oak,  walnut, 
and  pine.  The  oak  was  increased  in  strength  five- 
ninths,  wahiut  one-half,  two-fifths  for  pine,  and  more 
than  one-fifth  for  elm.  These  are  but  preliminary 
experiments,  which  may  lead  to  very  important  re- 
sults, and  are,  therefore,  interesting  to  architects 
especially.  By  this  process  the  fibres  of  the  wood 
are  drawn  closer  together,  and  maple  and  pine 
treated  in  the  steam,  at  a  temperature  of  487°,  were 
rendered  far  more  valuable  for  musical  instruments 
than  by  any  other  process  heretofore  known.  This 
is  valuable  information  to  all  musical  instrument 
makers.  Who  knows  but  this  is  a  discovery  of  the 
Venetian  fiddle-makers'  great  secret. 

Wooden  Roof  Shingles. 

One  of  the  most  valuable  applications  of  the  soluble 
glass  may  be  recommended  for  shingles  and  wooden 
roofs  of  farmhouses  in  the  country  and  near  railroads, 
where  the  sparks  of  the  locomotives  have  frequently 
caused  deflagrations  and  destruction  of  property. 

The  operation  is  quite  simple  and  the  expense  but 


150 


SILIFICATION  OF  WOOD. 


trifling  ;  the  process  has  already  been  described,  but 
it  may  be  still  more  simplified  in  the  following  man- 
ner : 

After  the  steaming  of  the  shingles  in  boilers  or  in 
tanks,  where  steam  of  250  to  350°  is  led  into  them ; 
they  are  dried  and  thrown  into  aweak  solution  of  liquid 
silica,  standing  about  25°  B,  in  which  they  are  left 
for  24  hours,  when  they  are  taken  out  and  exposed 
to  the  air.  Before  they  are  quite  dry,  a  weak  solu- 
tion of  chloride  of  calcium  is  thrown  over  them  or 
sprinkled  over  them  with  a  broom.  When  quite 
dry  they  are  fit  for  use.  They  will  not  burn  nor  be 
ignited  with  the  sparks ;  if  exposed  to  a  direct  fire, 
will  not  light  in  a  surrounding  fire.  An  intense  heat 
of  long  duration  may  char  them  on  the  surface  ;  they 
are,  however,  quite  safe  from  any  inflamation. 

The  Preservation  of  Wood  by  Immp:esion. 
The  processes  for  the  preservation  of  wood  may  be 
divided  into  three  groups,  namely :  processes  by 
immersion  ;  processes  by  pressure  in  closed  vessels, 
(which  are  exclusively  employed  for  dry  wood,)  and 
processes  founded  on  the  displacement  of  the  sap 
(which  are  only  employed  for  green  wood.)  In  the 
present  article  we  shall  describe  the  methods  by  im- 
mersion. 

Attempts  to  impregnate  wood  by  the  method  of 
immersion  were  the  first  experiments  undertaken. 
As  early  as  1740,  Fagol,  a  Frenchman,  tried  to  im- 


SILIFICATION  OF  WOOD. 


151 


pregnate  wood  with  alum,  sulphate  of  iron,  and 
various  other  substances,  in  solutions  of  which  he  im- 
mersed it  for  several  day.  In  1Y56,  Haller  recom- 
mended vegetable  oil  for  the  same  purpose.  In 
176 7,  Jackson  indicated  the  use  of  a  solution  of  sea 
sale,  to  which  sulphate  of  iron  and  magnesia,  alum, 
lime,  and  potassa  were  to  be  added.  In  1779,  Pallas 
proposed  to  mineralize  wood  by  dipping  it  first  in  a 
solution  of  green  copperas  and  afterward  in  milk  of 
lime.  In  1830,  Kyan  in  England,  tried  to  preserve 
wood  by  simply  immersing  it  in  a  solution  containing 
two  per  cent  of  bichloride  of  mercury.  Not  long 
since,  experiments  were  made  in  France  and  Ger- 
many with  a  large  number  of  railroad  ties,  by  keep- 
ing them  several  hours  in  a  solution  containing  1.5 
per  cent,  of  sulphate  of  copper,  at  a  temperature  of 
160*^  Fahr.  This  preparation  is,  however,  altogether 
insufficient  for  the  preservation  of  fir  or  pine  wood, 
and  in  general  for  light  woods  which  contain  a  large 
amount  of  nitrogenous  substances  ;  but  it  seems  to 
increase  considerably  the  durability  of  oak.  The 
wood  is  thus  surrounded  by  a  very  thin  coating, 
which  is  not  liable  to  decay  nor  to  the  attacks  of 
insects,  and  which  retards  the  alteration  of  the  inner 
parts.  These  are,  however,  not  impregnated  at  all 
by  the  anticseptic  liquid  ;  they  preserve  their  germs 
of  putrefaction,  which  develop  the  easier  the  more 
the  injected  surface  is  removed,  whether  by  friction 


152 


SILIFICATION  OF  WOOD. 


blows,  or  the  driving  in  of  nails.  The  decay  com- 
mences then  at  the  denuded  points,  and  propogates 
itself  tow^ard  the  central  parts. 

Baron  Champtj  also  indicated  a  method  for  pre- 
serving wood,  by  dipping  it  when  green  into  suet  of 
200"  Fahr,  The  water  and  the  gases  which  are  in- 
closed in  the  vegetable  tissue  escape,  and  by  the  con- 
densation which  follows  upon  cooling,  a  vacuum  is 
produced,  into  which,  by  the  pressure  of  the  atmo- 
sphere, the  suet  is  made  to  penetrate.  Mr.  Pay  en 
made  use  of  this  experience,  substituting  for  the  suet, 
rosin,  heated  to  300"  Fahr.,  and  in  this  manner  in- 
troduced into  a  small  poplar  tree  three-fifths  of  its 
weight  of  rosin. 

Decay  of  W ood  and  Processes  for  Preserving  it. 

According  to  the  experiments  which  were  made  by 
De  Saussure,  in  the  beginning  of  this  century,  it 
would  seem  that  the  decay  of  woody  fibre  was  ex- 
clusively caused  by  the  action  of  air  and  water.  On 
exposing  moist  wood  to  the  action  of  oxygen  gas,  he 
found  that,  for  every  volume  of  oxygen  absorbed  by 
the  wood,  one  volume  of  carbonic  acid  was  disen- 
gaged. It  is  now  conceded  that  it  is  the  hydrogen  of 
the  fibre  which  is  oxidized  at  the  expense  of  the 
oxygen  of  the  atmosphere,  while  the  carbonic  acid 
is  solely  formed  from  the  elements  of  the  wood,  or 
that  the  process  is  simply  a  separation  of  a  portion  of 


8ILIFICATI0N  OF  WOOD. 


153 


the  carbon  of  tlie  wood  by  direct  oxidation  ;  and  it 
would  seem,  from  the  experiment  mentioned,  that 
the  first  and  only  cause  of  the  decay  of  vegetable 
tissue  must  be  ascribed  to  the  affinity  of  oxygen  for 
the  elements  of  the  latter. 

Such  cases  of  slow  decomposition  have  indeed  also 
been  distinguished  by  the  name  eremacausis^  a  term 
composed  of  two  Greek  words,  and  meaning  to  burn 
by  degrees. 

The  above  explanation,  however,  scarcely  holds 
good  in  all  cases,  it  is  now  known  that,  in  dry  air, 
woody  fibre  may  be  preserved  without  decaying  for 
thousands  of  years;  and,  under  water,  in  certain  con- 
ditions, it  appears  to  be  equally  durable.  One  must, 
therefore,  look  for  some  other  cause  to  explain  the 
transformation  of  woody  fibre.  Such  a  one  presents 
itself  in  the  fact  that,  when  wood  is  exposed  for  some 
weeks  to  running  water,  or  if  it  is  boiled  in  water  and 
afterward  dried  until  the  original  weight  is  restored, 
it  is  rendered  therby  considerably  more  durable. 

The  cause  of  the  transformation  in  question  must,, 
therefore,  be  sought  in  a  substance  which  is  removed 
by  the  dissolving  action  of  water  in  the  experiment 
mentioned.  By  further  investigation,  this  substance 
is  found  to  consist  of  the  albumen  of  the  sap,  which 
is  distributed  throughout  the  cellular  tissue.  Like 
the  animal  albumen,  as  the  white  of  eggs,  which  it 
closely  resembles  both  in  properties  and  composition, 


t 


154  SILIFICATION  OF  WOOD. 

the  vegetable  albumen  is  exceedingly  liable  to  decom- 
position. In  this  state,  it  acts  like  a  ferment,  induc- 
ing the  decay  of  other  bodies,  according  to  the  phy- 
sical law  propounded  in  another  application  by  Lap- 
lace and  Berthollet,  namely,  that  a  molecule  set  in 
motion  by  any  power  can  impart  its  own  motion  to 
another  molecule  with  which  it  may  come  in  con- 
tact. 

Among  the  bodies  most  prone  to  decomposition  is 
the  sugary  element,  which  is  first  dissolved.  Then 
the  growth  of  fungi  generally  begins,  and  the  putre- 
faction proceeds  step  by  step.  It  may,  therefore,  be 
considered  that  the  spontaneous  decomposition  of 
the  vegetable  albumen  is  the  primary  cause  of  the 
decay  of  wood.  It  is,  indeed,  found  that  those  kinds 
of  wood  which  contain  the  smallest  quantity  of  albu- 
minous matter  and  amylum  are  the  most  durable. 
Especially  is  this  the  case  with  a  certain  tree  of  the 
acacia  tribe,  the  locust,  and  the  cedar,  which  resist 
decomposition  in  situations  where  all  other  kinds  of 
wood  soon  decay. 

In  order,  then,  to  find  out  whether  a  certain  kind 
of  wood  is  especially  fitted  for  building  purposes, 
the  quantity  of  albumen  present  in  the  fibre  should 
be  ascertained  by  analysis.  M.  Payen  recommends, 
for  this  purpose,  to  digest  the  wood  in  a  dilute  solu- 
tion of  caustic  alkali — this  soda,  or  potassa — which 
has  no  action  on  the  woody  fibre,  but  only  dissolves 


SILIFICATION    OF  WOOD. 


155 


the  albumen.  Hence,  the  quantity  of  the  latter  may 
be  estimated  by  washing,  drying,  and  weighing  the 
wood  after  the  experiment  has  been  made. 

Methods  of  Preserving.  Wood. 

If  the  primary  cause  of  the  decay  of  woody  libre 
be  its  contact  with  putrefying  albumen,  a  means  of 
preserving  is  naturally  suggested  in  the  removal  of 
the  albumen  ;  or  else  in  so  combining  it  with  other 
substances  that  it  forms  a  compound  which  is  insol- 
uble in  water,  and  not  susceptible  to  spontaneous 
decomposition.  It  would  seem  that  the  solubility  of 
the  albumen  in  cold  and  tepid  water  would  afford  a 
simple  means  of  withdrawing  this  clement  of  decom- 
position, and  thus  of  preserving  timber  ;  but  this  pro- 
cess, though  effectual,  is  by  far  too  slow  to  be  practi- 
cable. 

The  most  ancient  method  of  guarding  wood  against 
decay  consists  in  the  application  of  an  external  coat- 
ing of  oils  and  resins  or  a  hot  solution  of  silicate  of 
soda,  according  to  the  author  of  this  treatise  in 
connection  with  that  of  chloride  of  calcium  and 
carbolic  acid.  If  tlio  wood  is  dry,  and  otherwise 
in  a  sound  state,  and  also  not  exposed  to  abra- 
sion, a  perfect  protection  may  be  afforded  in  this 
way.  A  more  elFectual  mode  of  preserving  it,  how^- 
ever,  consists  in  its  immersion  in  a  hot  solution  of  the 
respective    preservative.     This    may  either  serve 


156 


SILinCATION    OF  WOOD. 


simply  for  filling  the  pores,  or  for  forming  a  com- 
pound with  the  albuminous  matters,  which  has  the 
property  of  not  being  decomposed.  Both  ends  may 
be  arrived  at  by  one  and  the  same  substance. 

Impregnation  of  Wood  by  Pressure. 

This  method  was  not  practiced  to  any  great  extent 
previous  to  the  close  of  the  last  century.  In  the  in- 
quiry into  the  means  which  have  been  taken  to  pre- 
serve the  British  navy,  particularly  from  dry  rot,  a 
volume  has  been  produced,  which  affords  a  splendid 
account  of  all  that  had  been  done  up  to  that  time  in 
the  direction  of  wood  preservation.  The  author 
gives  a  full  account  of  the  action  of  about  forty  sub- 
stances, among  which  may  be  mentioned,  solutions 
of  sulphate  of  copper,  sulphate  of  iron,  alum,  borax, 
lime,  corrosive  sublimate,  and  other  forms  of  mercury, 
preparations  of  zinc  and  iron,  sea-salt,  creosote,  lin- 
seed-oil, coal  and  wood  tar,  and  wax.  As  it  is  how- 
ever, not  the  intention  of  these  articles 'to  do  dwell 
upon  things  of  the  past,  but  upon  things  of  the  pre- 
sent, the  writer  may  pass  to  the  description  of  some 
modern  processes. 

The  apparatus  now  used  in  France  for  the  satura- 
tion of  timber  with  preservative  agents  is  described 
as  follows :  It  consists  of  a  cast-iron  cylinder,  which 
is  connected  by  means  of  a  tube  with  a  condenser. 
Both  are  placed  in  a  vertical  position.    The  opera- 


SIIJFICATION  OF  M^OOD. 


157 


tiori  is  begun  by  introducing  the  timber  into  the  cast- 
iron  cylinder,  together  with  the  preservative  material. 
The  latter,  however,  is  not  altogether  to  rise  to  the 
entire  height  of  the  stem.  The  receptacle  of  the 
wood  is  hereupon  closed,  and  connected  with  the 
condenser.  A  vacuum  is  then  produced  in  the  latter, 
.  which  is  accomplished  by  introducing  alternate  steam 
and  sprays  of  water  into  it.  After  this  the  stop-cock 
of  the  tube  connecting  the  two  cylinders  is  opened, 
when  the  air  passes  from  the  receptacle  into  the  con- 
denser. This  operation  is  repeated,  until  the  pres- 
sure in  the  cylinder  is  less  than  fifteen  decimetres. 
The  same  is  kept  up  for  several  minutes,  in  order  to 
let  the  air  of  the  timber  have  time  to  escape.  The 
connection  between  the  receptacle  and  the  condenser 
is  finally  closed.  A  pump  is  then  set  in  motion,  by 
means  of  which  the  preservative  agent  is  made  to 
penetrate  the  pores  of  the  vegetable  tissue,  until  the 
pressure  stands  at  that  of  ten  atmospheres.  This  is 
maintained  for  various  lengths  of  time,  according  to 
the  nature  of  the  wood  and  the  liquid,  but  six  hours 
are  generally  sufficient.  After  this  the  air  is  gradually 
allowed  to  enter,  while  the  preservative  liquor  is  left 
to  run  away. 

For  the  relative  claims  of  wood  and  rfietal  as  ma- 
terials for  rails^  many  facts  ought  to  be  considered ; 
wood  is  exempt  from  the  inconveniences,  dangers 
and  expenses  incidental  to  contraction  and  expansion 

7 


158 


SILIFICATION  OF  WOOD. 


under  variations  of  atmospheric  temperature.  Metal 
at  an  extreme  low  point  fractures,  and  most  lamen- 
table casualties  result ;  while  under  the  fervid  heat 
of  90  to  170^,  the  expansion  of  iron  is  so  great  as  to 
displace  the  work  on  which  the  rails  repose,  and  thus 
render  the  whole  fabric  unsteady  and  unsafe. 

From  the  Report  on  Wooden  Railways  the  follow- 
ing extract  is  made  : — "  The  length  of  the  experi- 
mental line  laid  down  near  Yauxhall  bridge  was  174 
yards,  with  gradients  of  1  in  95,  1  in  22,  and  1  in  9, 
and  a  curve  of  720  feet  radius.  The  speed  attain- 
able on  so  short  a  line  was  of  course  limited ;  but  the 
power  given  to  the  engineer  by  the  bite  of  the  wheel 
on  the  wood  (for  the  line  was  laid  with  wooden  rails) 
enabled  him  to  drive  at  the  rate  of  twenty-four  miles 
an  hour,  and  to  stop  the  carriage  in  a  distance  of 
twenty-four  yards.  In  the  presence  of  several  engi- 
neers the  carriage,  laden  with  passengers,  ascended  an 
incline  of  1  in  9,  the  rails  being  in  a  very  bad  state 
at  the  time  from  damp  weather. 

"  Since  the  introduction  of  wood  paving,  it  may  be 
calculated  that  a  saving  of  one-half  has  been  effected 
in  the  wear  and  tear  of  carriages,  horses,  and  harness 
in  those  districts  where  it  has  been  adopted  ;  a  saving 
equally  great  can  be  made  in  the  construction  of 
railroads  by  the  substitution  of  wood  for  iron  rails. 
The  rails  may  be  made  of  beech  or  other  hard  Eng- 
lish timber,  six  or  eight  inches  square,  let  into  wooden 


SILIFICATION  OF  WOOD. 


159 


sleepers,  and  secured  by  wooden  wedges,  forming  one 
great  frame,  or  wooden  grating  of  longitudinal  and 
cross  sleepers. 

"  An  engine  weighing  ten  tons  running  on  wood 
will  have  more  tractive  power  than  one  weighing 
eighteen  tons  running  on  iron  ;  and  as  the  concussion 
and  abrasion  on  wood  is  so  trifling,  carriages  built  to 
weigh  one  and  a  half  tons  will  be  as  strong  as  those 
having  to  run  on  iron  weighing  three  tons.  An  im- 
portant question  connected  with  this  subject  is  the 
durability  of  the  material  of  which  the  rails  are  com- 
posed. The  engine  employed  for  the  experiment 
weighed  about  six  tons  ;  it  passed  over  the  rails  dur- 
ing the  two  months  it  ran  8,000  times  in  every 
variety  of  weather,  which  is  equal  to  nearly  seven 
years  traffic  of  twelve  engines  per  day.  The  rails 
consisted  of  Scotch  flr,  about  nine  feet  long  and  six 
inches  square ;  and  yet,  upon  examining  them  after 
the  severe  test  to  which  they  had  been  subjected,  they 
exhibited  no  appearance  of  wear  from  the  friction  of 
the  wheels  on  the  upper  surface,  as  the  saw  marks 
were  not  effaced. 

"  The  capability  of  wood  to  sustain  the  strain  to 
which  it  must  necessarily  be  exposed,  especially  when 
moving  over  it  at  higli  velocities,  has  been  satisfac- 
torily proved  by  the  experience  of  the  Great  Western 
and  other  railways,  wliere  continuous  longitudinal 
sleepers  of  wood  have  been  employed,  and  experience 


160 


SILIFICATION  OF  WOOD. 


has  shown  that  the  solidity  of  the  road  is  much 
greater  than  when  the  iron  rails  were  attached  either 
to  stone  locks  or  transverse  wooden  sleepers.  In 
proof  that  wooden  rails  cut  from  beech  will  bear  the 
wear  and  tear  of  trains  passing  over  it,  it  is  well  known 
that  beech  cogs  have  proven  to  last  eighteen  to 
twejity  years  when  working  in  gear  with  an  iron 
wheel.  The  rails  on  the  Yauxhall  line  were  pre- 
pared by  Payne's  patented  process  for  preventing 
dry-rot  and  decay  of  timber.  Scotch  fir,  if  subjected 
to  pressure,  will  crush  at  ten  tons,  while  beech  (the 
wood  recommended  for  railways)  will  bear  a  pressure 
of  eighty-two  tons  before  it  begins  to  yield. 

"  Experience  having  confirmed  the  capability  of 
Scotch  fir  to  withstand  the  trafiic  of  twelve  engines 
per  day  for  seven  years,  without  any  visible  wear,  it 
would  be  difficult  to  say  how  long  the  rails  cut  from 
beech,  sustaining  eighty-two  tons  pressure,  would 
last.  Some  of  the  impediments  with  which  railroads 
have  to  contend  are  the  undulations  of  the  country, 
and  the  necessity  of  diverging  from  a  right  line  in 
order  to  obtain  the  traffic  of  important  towns.  These 
obstacles  can  only  be  overcome  by  an  outlay  of  capi- 
tal, in  making  the  required  excavations  and  embank- 
ments, or  by  the  oftentimes  ruinous  system  of  tun- 
nelling, and  after  all,  inclines  of  greater  or  less  gra- 
dients are  unavoidable,  and  prevent  the  line  working 
economically.    Curves  on  iron  railroads  are  highly 


SILIFICATION  OF  WOOD. 


161 


prejudicial,  especially  if  the  radius  be  small,  as  the 
wear  and  tear  becomes  proportionably  increased. 

"  Now,  by  the  introduction  of  the  proposed  plan,  the 
evils  arising  from  the  obstacles  alluded  to  would  be 
very  materially  diminished ;  for,  in  the  first  place, 
tbe  surface  resistance  obtained  by  the  elastic  char- 
acter of  wooden  rails,  enables  a  train  to  be  propelled 
up  inclines  with  much  greater  facility  and  ease  than 
on  rails  constructed  of  iron.  The  adyantages  of 
wooden  railways  thus  constructed,  in  point  of 
economy,  comfort,  durability,  and  as  feeders  to  the 
great  and  central  lines  already  formed,  must  be  ap- 
parent to  every  one  who  has  given  the  subject  any 
consideration. 

"  The  result  of  a  series  of  experiments,  made  to 
ascertain  the  proportionate  power  of  the  bite  of  wood 
over  iron,  has  fully  borne  out  the  assertion  of  the 
patentee,  that  the  bite  of  the  driving-wheel  on  wood 
is  nearly  double  that  on  iron.  On  the  surface  of  an 
iron  wheel  four  feet  in  diameter,  a  lever  eight  feet 
long  was  placed,  with  a  weight  of  seven  pounds  at- 
tached to  the  leyer,  three  feet  from  the  centre  of  the 
axis  of  the  wheel ;  tlie  surface  of  the  lever  being  iron 
at  the  tangent  of  the  wheel,  it  required  a  weight  of 
twenty-eight  pounds  attached  to  the  crank  to  make 
it  revolve.  On  substituting  a  wood  surface  for  the 
iron  one;  it  required  a  weight  of  forty-two  pounds. 
Another  experiment  confirmed  the  result  with  the 


162 


SILIFICATION  OF  WOOD. 


iron  surface  ;  a  weight  of  twenty-eight  pounds  at- 
tached to  the  spoke  of  the  wheel,  at  a  distance  of  six 
and  three-quarter  inches  from  the  centre,  made  it  re- 
volve ;  whilst  with  a  wooden  surface,  it  required  the 
Barae  weight  to  be  attached  to  the  spoke  at  a  distance- 
of  eleven  and  a  half  inches  from  its  centre,  thus 
clearly  demonstrating  the  power  obtained  by  the 
bite  of  the  wood  is  nearly  double  the  bite  of  iron. 

"  Mr.  J.  M.  Mason,  (of  Trent  notoriety)  when  in 
England,  devoted  some  attention  to  Prosser's  system 
of  wooden  rails,  with  a  view  to  their  use  in  the  South- 
ern States  during  the  war,  and  in  a  letter  to  Mr.  C. 
J.  Bloomiield,  he  writes,  '  I  was  most  strongly  im- 
pressed with  i\iQ\r  feasibility  and  durahility .''  " 

Timber  Rot  and  Seasoning. 

It  is  generally  supposed  that  the  rotting  of  timber 
is  merely  induced  by  the  action  of  the  oxygen  of  the 
air.  From  analysis  made  of  sound  and  decayed  oak, 
it  has  been  shown  that  for  every  two  equivalents  of 
hydrogen  oxidized  by  the  air,  one  equivalent  of  car- 
bonic acid  had  separated.  It  may  therefore  be  in- 
ferred that  the  decay  or  rot  of  timber  does  not  arise 
from  fermentation  ;  but  is  rather  a  chemical  process. 
Otliers  admit  that  microscopical  parasities  of  vege- 
table nature  play  an  important  part  in  the  decay  of 
wood ;  but  consider  the  presence  of  albuminious 
matter  in  the  sap  as  necessary,  which,  according  to 


6ILIFICATI0N  OF  WOOD. 


163 


them,  must  also  be  first  in  a  state  of  decomposition 
before  it  allows  the  growth  of  those  organisms.  Jn 
order  to  throw  light  upon  this  most  important  sub- 
ject, we  propose  first  to  tabulate  a  number  of  well- 
observed  facts.  Sound  timber,  when  immersed  in 
water,  without  access  of  air,  will  withstand  decay  for 
almost  an  unlimited  time.  This  is  proved  by  the 
piles  upon  which  the  dwellings  on  the  Canaries  rest, 
which  were  erected  in  the  time  of  the  Conquest  in 
1402,  they  being  just  as  sound  now  as  if  they  had 
been  freshly  felled.  Roots  of  trees  that  have  been 
submerged  in  marches  are  rarely  found  decomposed. 
This  is  stated  to  be  the  case  with  the  utensils  dis- 
covered in  the  lake  dwellings  of  Switzerland,  Bavaria, 
and  Lombardy,  which  must  be  at  least  ten  thousand 
years  old.  Ilartig  also  describes  a  cypress-stem  with 
over  three  thousand  rings,  representing  the  same 
number  of  years,  which,  though  submerged,  had  only 
partially  turned  into  brown  coal. 

With  rv^spect  to  the  action  of  the  atmospheric  air,  it 
may  be  asserted  that  the  same,  even  when  moist,  will 
not  produce  rot,  if  the  wood  has  been  well  steamed, 
or  exposed  to  the  action  of  running  water  for  a  suffi- 
cient length  of  time.  In  England  it  is  customary  to 
lay  the  timber  destined  for  threshing-floors  and 
wainscoating  in  fresh  water  for  several  weeks.  When 
again  dry  and  not  exposed  to  damp,  such  timber  will 
endure  for  an  incredible  period  of  time. 


164 


SILIFICATION  OF  WOOD. 


This  tends  to  demonstrate  the  fact  that  the  sub- 
stance which  induces  decay  must  be  foreign  to  the 
timber  itself.  This  substance  is  the  juice  that  is 
chiefly  contained  in  the  vascular  tissue,  which  forms 
a  link  between  the  bark  and  the  wood.  The  compo- 
sition of  this  sap  varies  according  to  circumstances, 
as  the  variety  of  the  tree,  climate,  season,  ground, 
etc.    The  following  are  analyses  of  the  sap  : 


CD 

l.l . 

In  100  Parts. 

Elm 
ique 

■oil 

ap  of 
Vai 

p- 

03 

• 

m 

5^ 

3T06(a) 

16.14 

4.37(&) 

13.34 

6.31 

20.93 

30.57 

'7*02 

3.56 

Organic  Substance  (not  determined),. 

o.io 

Potassa  with  Organic  Acid,.  ,  

0.87 

 * 

0.10 

Extractive  Matter  and  Salts,  

33!70 

98 '.93 

62.66(c) 

100.00 

100.00" 

100.00 

(a)  Gluten  and  Albumen,  according  to  Solly,  {b)  Dextrin  and 
Salt,    (c)  Water  and  Butyric  Acid. 

Remarks. — The  Cow  Tree  {Qalactodendron)  is  a  native  of  the 
Cordilleras  of  Venzuela ;  it  furnishes,  by  incision,  an  enormous 
quantity  of  a  white,  thick  liquid,  which  has  the  taste  and  some  of 
the  qualities  of  real  cow's  milk.  The  Antiaris  toxicaria  belongs 
to  the  same  family  as  the  former — namely,  to  the  nettle-worts,  and 
it  is  singular  that  it  furnishes  a  most  deadly  poison,  which  has 
been  the  subject  of  the  most  harrowing  stories.  (Jussieu ;  Elements 
of  Botany.) 


SILIFICATION    OF  AVOOD. 


165 


Unfortunately  we  possess  only  one  analysis  of  a 
tree  indigenous  to  North  America ;  however,  the 
same  tends  to  show  that  the  amount  of  albumen,  if 
the  non-determined  organic  matter  must  be  con- 
sidered as  such,  is  exceedingly  small,  and  with  re- 
spect to  the  other  trees,  these  analysis  prove  that  the 
albumen  does  not  constitute  the  chief  part  among  the 
ingredients  of  the  juice.  How  unjustifiable  it  is, 
therefore,  to  attribute,  in  every  instance,  the  decay  of 
timber  to  the  albumen  present  in  the  sap,  as  if  it  was 
the  only  substance  liable  to  spontaneous  decomposi- 
tion, or  afi'ording  the  vegetation  of  fungi  and  lichens ! 
How  unfounded  is  the  assertion  of  Mr.  Joseph  B. 
Lyman,  who,  in  an  article  on  the  preservation  of  tim- 
ber, states  that  "wood  is  mainly  made  up  of  woody 
fibre  and  a  substance  full  of  nitrogen  "  !  {vide  Work- 
ing Farmer,  November  1st,  1868.) 

In  regard  to  the  amount  of  sap  and  air  contained 
in  the  oak  and  poplar,  we  possess  the  following  data 
from  Count  Rumford : 

Wood.         Sap.  Air. 

Oak  0.39353      0.36122  0.24525 

Poplar  0.24289      0.21880  0.53831 

The  German  botanist,  Schacht,  in  all  instances  of 

decayed  timber,  has  met  with  fungi  and  lichens. 

The  destruction  of  timber  by  decay,  after  the  same 

has  been  hewn,  must,  therefore,  be  considered  as 

being  produced  by  similar  causes  which  brought  on 

the  disease  of  the  vine,  potato,  mulberry  trees,  and 


166 


8ILIFICATI0N  OF  WOOD. 


other  cultivated  plants,  which  make  the  years  1845, 
'48,  '53,  '57,  and  others  forever  painful  to  the 
memory. 

That  the  juice  should  be  in  a  state  of  decomposition 
before  being  capable  of  generating  those  organisms 
seems  doubtful,  since  this  has  not  been  found  the  case 
in  other  and  well -studied  modes  of  fermentation.  The 
morel,  a  species  of  mushroom,  will  also  attack  per- 
fectly sound  wood.  Hand  in  hand  witli  the  spread  of 
the  fungi  continues  the  decomposition  of  the  ligneous 
tissue.  Access  to  moisture  and  air,  as  also  a  certain 
degree  of  heat,  are  necessary.  In  regard  to  the  air, 
fungi  require  oxygen  for  their  generation.  When 
air-dried,  steamed,  or  chemically  treated  and  after- 
ward dried  wood  commences  to  rot,  it  is  a  sign  that 
moisture  has  again  penetrated  ;  for  it  is  scarcely  to  be 
admitted  that  in  all  these  cases  the  sap  had  been  en- 
tirely removed.  Timber  decomposes  the  easier  the 
more  sap  it  contains,  and  if  green  trees  are  hewn 
when  the  vessels  are  overflowing  with  juice,  one  may 
look  with  certainty  for  diminished  durability  of  the 
timber.  Timber  is  not  always  the  more  durable  the 
more  dense  it  is,  but  rather  when  the  even  fineness  of 
the  grain  continues  to  the  pith  of  the  stem. 

The  Roman  historian,  Pliny,  considers  the  resini- 
ferous  woods  as  the  most  durable.  Indeed,  nature 
shows  that  this  is  frequently  the  case.  The  resinifer- 
ous  red  and  white  pines  of  Oregon  and  California  are 


SILIFICATION  OF  WOOD. 


167 


considered  first-class  ship  timber,  so  much  so  that 
entire  vessels  have  been  constructed  from  the  denser 
qualities.  The  yellow  or  long-leaved  pine,  in  dry- 
situations,  is  extremely  durable,  and  is  preferred  to 
oak  of  any  kind  where  a  lighter  yet  solid  wood  is  re- 
quired. The  white  or  northern  pine,  which  grows 
abundantly  in  every  northern  State  of  the  Union, 
from  Maine  to  Minnesota,  reaching  often  to  an  alti- 
tude of  one  hundred  and  eighty  feet,  with  a  diameter 
of  six  feet  or  more,  is  said  to  retain  its  properties  as 
long  as  the  very  best  description  of  oak.  ■ 

The  fact  that  dried  timber  is,  for  nearly  every  pur- 
pose, far  superior  to  green,  has  led  to  its  being  dried 
in  the  opeji  air,  or  in  confined  rooms  by  means  of 
heated  air,  or  mixtures  of  air  and  steam.  The  first 
method  is  termed  seasoning.  Newly  felled  wood,  in 
order  that  it  may  season  properly,  should  be  pro- 
tected from  rain,  sun,  and  strong  winds.  It  should 
be  piled  up  so  that  a  circulation  of  air  can  take  place 
from  beneath. 

The  shed  in  which  the  timber  is  dried  should  be 
paved  and  provided  with  sewers.  Moreover,  the  re- 
lative position  of  the  pieces  of  timber  should  be 
changed  from  time  to  time  during  the  seasoning 
process.  The  necessary  time  for  seasoning  varies  from 
two  to  four  years. 

The  proportion  in  which  the  woody  fibre  and 
water   are  to  each  other   is  very  different.'  It 


168 


SILIFICATION    OF  WOOD. 


varies  according  to  the  degree  of  dryness  and  the 
nature  of  the  wood  itself.  According  to  Schiibler 
and  Neufter,  we  have  for  newly  felled  woods  the  fol- 
lowing table : 

WOOD.  WATER. 

Hornbeam.  18.6  per  cent. 

Willow  26.0 

Sycamore  27.0  " 

Ash  28.7 

Birch  30.8 

Oak  34.7 

PedichOak  35.4 

White  Fir  37.1 

Pine  39.7 

Red  Beech  39.7 

Alder  41.6 

Asp   43.7 

Elm  44.5 

Red  Fir  45.2 

Lime  Tree  47.1 

Italian  Poplar  48.2 

Larch  48.6 

White  Poplar  50.6 

Black  Poplar  51.8 

The  amount  of  water  in  wood,  after  one  year's  dry- 
ing in  the  air,  ranges  from  20  to  25  per  cent.,  and 
when  perfectly  air-dry,  as  it  is  called,  it  still  holols 
ftom  ten  to  fifteen  per  cent. 

The  specific  weight  of  newly  felled  timber  ranges 
from  0.85  to  1.05;  that  of  air-dried  timber  from  0.45 
to  0.Y5,    The  weight  of  one  cubic  foot  of  newly  cut 


SILIFICATION  OF  WOOD. 


169 


native  timber  would  thus  range  from  fifty  to  sixty- 
five  pounds,  while  that  of  seasoned  wood  would  vary 
from  twenty-eight  to  forty -seven  pounds.  The  total 
expulsion  of  moisture  by  means  of  air-drying,  accord- 
ing to  the  experiments  of  Rum  ford,  takes  place  only 
at  280®  Fahrenheit.  But  even  if  thus  completely 
dried,  and  then  exposed  again  to  the  atmosphere,  it 
absorbs  nearly  five  per  cent,  of  water  during  the  first 
three  days,  and  continues  to  absorb  until  it  contains 
from  fourteen  to  sixteen  per  cent.,  after  which  it 
becomes  very  hygroscopic,  losing  or  absorbing  water 
according  to  the  state  of  the  atmosphere.  Indeed,  it 
appears  that  this  property  is  never  entirely  removed. 
According  to  the  author  of  an  article  on  "  Wood  "  in 
Appleton^s  Dictionary  of  Mechanics^  some  bog  oak, 
supposed  to  have  been  buried  on  the  island  of  Sheppy 
not  less  than  a  thousand  years,  was  dried  for  a  good 
many  months,  and  then  used  for  the  manufacture  of 
furniture.  When  divided  into  the  small  pieces  re- 
quired for  the  work,  it  was  still  found  to  shrink. 
With  regard  to  the  shrinkage  after  one  year's  season- 
ing, it  ranges  from  five  to  twenty  per  cent.,  and  after 
a  seasoning  of  four  years  from  thirteen  to  thirty -two 
^er  cent. 

W.  W.  Bates,  of  Chicago,  111.,  contributes  the  fol- 
lowing data  upon  the  shrinkage  of  green  North  Caro- 
lina live  oak,  cut  at  different  seasons  of  the  year,  in 
the  Report  of  the  Commissioner  of  Agriculture  for 


170 


SILIFICATION  OF  WOOD. 


the  year  1866.  The  shrinkage  after  one  year's  sea- 
soning was  as  follows : 

Loss  of  weight  in  summer-cut  logs,  in  bark. .  .5  per  cent. 
IjOSS  of  weight  in  winter-cut  logs,  in  bark. .  .  .6  " 

Difference  in  favor  of  summer-cut  logs. . .  1  per  cent. 
Loss  of  weight  in  summer-cut  squared  timber. 5  per  cent. 
Loss  of  weight  in  winter-cut  squared  timber  .  5  " 

Difference   0  per  cent. 

The  shrinkage  after  four  year's  seasoning  gave : 

Loss  of  weight  in  summer-cut  logs,  in  bark. .  .23  per  cent. 
Loss  of  weight  in  winter-cut  logs,  in  bark. .  .  .27  " 

Difference  in  favor  of  summer-cut  logs. ...  4  per  cent. 
Loss  of  weight  in  summer-cut  squared  timber. 23  per  cent. 
Loss  of  weight  in  winter-cut  squared  timber.  .22  " 

Difference  in  favor  of  winter  cut  timber. .  .  1  per  cent. 

The  drying  of  lumber  in  confined  rooms  by  means 
of  hot  air,  or  steam  and  air  alternately,  is  now  largely 
practiced,  and  the  more  on  account  of  the  economy 
of  the  method  than  on  account  of  its  yielding  a  supe- 
rior product.  In  some  cases,  the  wood,  before  being 
exposed  to  artificial  heat,  is  subjected  to  a  longi- 
tudinal pressure,  in  order  to  rupture  the  cells  in 
which  the  moisture  is  confined,  to  the  end  that  it 
may  escape  more  freely  upon  the  application  of  heat. 
It  is  claimed  that  the  wood  is  thus  rendered  more 


SILIFIOATION  OF  WOOD. 


171 


valuable  for  nearly  all  the  purposes  for  which  it  is 
used,  but  particularly  for  the  hubs,  spokes,  and 
panels  of  carriages,  etc. —  Dr.  Ott^  in  Eng.  <&  Min. 
Joicrnal. 

PRESERVING  WOOD.  ROBBINs's  PROCESS. 

The  preservation  of  wood  constitutes  one  of  the 
most  important  questions  with  which  applied  chemis- 
try has  to  deal.  It  has  been  ascertained  by  careful 
statistics  that  the  wooden  structures  alone  on  the 
farms  of  this  country  cost  over  one  hundred  millions 
of  dollars  every  year  while  the  sleepers  on  the  rail- 
ways cost  twenty-five  millions  during  the  same  period 
of  time.  If  the  duration  of  all  this  wood  could  be 
doubled,  it  would  save  the  country  twelve  and  a  half 
millions  every  year  in  railroad  ties,  and  fifty  millions 
in  fence  and  farm  buildings.  At  the  same  time,  our 
woodlands  are  being  cut  down  with  fearful  rapidity. 
This  fact  assumes  great  importance  when  we  reflect 
that  there  exists  a  most  intimate  relation  between  the 
climate  of  a  country  and  the  extent  of  its  forests. 
This  becomes  at  once  evident  when  it  is  known  that 
the  springs  of  rivers  do  not  issue  from  subterranean 
reservoirs,  but  consist  chiefly  of  collections  of  atmo- 
spheric precipitates,  rain,  dew,  and  snow,  which  have 
percolated  from  higher  levels.  Kainless  regions  are 
always  deficient  in  woodland,  and  there  are  innumer- 
able instances  where  vast  and  fertile  tracks  of  land 


172 


SILIFICATION  OF  WOOD. 


have  been  changed  into  barren  and  unhealthy  desserts, 
simply  because  they  have  been  stripped  of  their 
forests.  Therefore,  in  lengthening  the  duration  of 
wooden  structures,  we,  at  the  same  time,  prevent  the 
destruction  of  our  forests,  thus  leaving  to  the  coming 
generations  the  same  resources  which  we  have  in- 
herited from  our  forefathers. 

We  now  propose  to  examine  the  process  of 
Mr.  Louis  S.  Robbins,  which  was  patented  in 
1865,  and  purchased  a  year  later  by  the  "J^ational 
Patent  Wood-Preserving  Company"  of  New- York. 
It  goes  also  under  the  name  of  the  "  oleagin- 
ous vapor  process,"  and  has  been  described  in  the 
daily  and  weekly  press,  under  the  title,  "  Discovery  of 
one  of  the  Lost  Arts  of  the  Egyptians."  The  process 
may  be  briefly  described  as  follows  :  The  wood  to  be 
treated  is  placed  in  an  iron  chamber,  which  is  con- 
nected with  a  still  containing  coal-tar.  To  the  latter 
heat  is  applied,  until  the  contents  have  reached  the 
temperature  of  600*^  Fahr.  The  inventor  not  only 
claims  that  the  thus  impregnated  wood  will  be  com- 
pletely protected  against  the  moisture  of  the  atmo- 
sphere, but  also  that  it  is  rendered  "nearly  as  inde- 
structible as  granite."  In  order  to  comprehend  this 
process,  it  is  necessary  that  we  should  examine  the 
nature  of  the  products  which  are  given  off  in  heating 
coal-tar,  and  the  changes  which  they  produce  on 


SILIFicATION  OF  WOOD, 


173 


entering  the  pores  of  the  woody  fibre.  Coal-tar  con- 
sists, as  is  well  known,  of  a  number  of  substances — 
acid,  basic  and  neutral ;  of  the  latter,  some  are  liquid, 
some  solid.  In  subjecting  tar  to  distillation,  the  first 
products  given  off  are  ammonia  and  probably  also 
permanent  gases ;  then  water  is  evolved,  together 
with  various  ammoniacal  substances,  and  a  brownish 
oil  of  a  noxious  smell  and  of  less  specific  gravity  than 
water.  The  latter  is  associated  with  the  so-called 
light  oils,  the  portion  in  which  they  are  contained 
being  generally  gathered  separately  in  tar  distille- 
ries. They  amount  to  from  five  to  ten  per  cent,  and 
when  the  temperature  has  reached  320°  Falir.,  it 
may  be  concluded  that  they  have  passed  over.  The 
oils  distilling  at  a  later  stage  contain  large  quantities 
of  naphthalin  and  paranaphthalin,  both  solid  hydrocar- 
bons, of  w^liich  the  first  appears  at  about  400°  Fahr. 
They  are  often  present  in  such  quantities  that  the 
condensed  distillate  assumes  the  consistency  of  butter. 
Carbolic  or  phenic  acid  is  given  olf  a  little  earlier,  but 
the  giving  off  of  naphthalized  oils  continues  up  to 
550^^  Fahr.,  wlien  a  resinous,  yellowish  product  ap- 
pears, which  can  be  easily  kneaded  between  the  fin- 
gers. The  remainder  is  the  black,  j)itchy  mass,  used 
in  the  construction  of  Nicholson's  pavement. 

Among  the  various  substances  here  enumerated, 
the  phenic  acid  alone  is  that  to  which  any  preserva- 
tive properties  can  be  ascribed.    It  has  been  deter- 


SILIFICATION  OF  WOOD. 


mined  that  tar  from  cannel  coal  contains  seven  per 
cent.,  that  of  Staffordshire  coal  four  and  a  half,  and 
tar  from  Newcastle  coal  two  and  a  half  per  cent,  of 
this  acid.  The  average  quantity  of  phenic  acid  in 
coal-tar  would  therefore  be  less  than  five  per  cent ; 
moreover,  it  is  never  found  in  the  free  state,  but  al- 
ways in  combination  with  bases,  whereby  its  effi- 
ciency is  greatly  impaired.  Again,  being  soluble  in 
fresh  and  salt  water,  it  is  easily  and  rapidly  washed 
out,  finally  leaving  the  wood  as  completely  liable  to 
decay,  as  well  as  to  destruction  by  insects,  as  it  was 
before  treatment.  These  facts  are  sufficient  to  justify 
us  in  drawing  the  conclusion  that  the  vapors  of  coal- 
tar  are  not  efficient  preservatives. 

This  fact  was,  indeed,  particularly  reported  upon 
by  the  Hutch  Government  Engineers.  (See  Dingier' s 
Polytechnic  Journal.)  They  discovered  that  after 
thirteen  months'  exposure,  piles  which  had  been  cre- 
osotized  under  Mr.  Bethel's  special  superintendence 
were  found  so  completely  free  from  the  impregnating 
material  that  the  teredo  navalis  had  eaten  up  and 
destroyed  these  to  a  thickness  of  one  inch  and  a  quar- 
ter. The  same  fact  was  also  reported  by  Mr.  Steven- 
son, the  famous  English  engineer,  in  the  case  of  the 
piles  and  wood-work  on  the  Woolwich  side  of  the 
Thames.  The  dead  oil  had  been  completely  washed 
out,  and  the  destruction  of  the  wood  by  decay  and  by 
worms  was  proceeding  at  such  a  rate  that  Mr.  Steven- 


SILIFiCATION  OF  WOOD. 


1Y5 


son  expected  to  see  the  piles  totally  destroyed  before 
the  expiration  of  three  years  from  the  time  when  they 
had  been  impregnated. 

Again,  for  many  very  important  purposes  this  pro- 
cess is  inapplicable,  on  account  of  the  intolerably 
offensive  smell  of  the  dead  oil  and  other  products  of 
the  dry  distillation  of  bituminous  substances. 

In  a  pamphlet  before  us,  it  is  stated  that  there  is 
no  record  in  the  books  of  any  thing  like  this  process 
having  ever  been  known  to  the  world  prior  to  its  dis- 
covery by  Mr.  L.  S.  Kobbins.  It  is  claimed  to  be  as 
new  as  was  the  sewing-machine  or  the  telegraph. 
We  presume  that  Mr.  Kobbins  did  not  know  of  the 
process  patented  by  Frantz  Moll,  in  England,  in  1835^ 
which  is  as  follows  :  The  wood  is  placed  in  a  close 
chamber,  which  is  connected  w^ith  one  or  m(5re  stills. 
The  operation  of  impregnating  is  begun  by  heating 
the  inside  of  the  chamber  by  a  steam  pipe  to  a  tem- 
perature sufficiently  high  to  maintain  the  vapors  con- 
taining the  phenic  acid  in  a  vaporized  state.  But  be- 
fore tliese  are  introduced,  the  watery  vapor  from  the 
damp  timber  is  allowed  to  escape,  after  which  heat  is 
applied  to  the  still  containing  the  light  hydrocarbon 
oils,  or  the  "  eupion,"  as  the  mixture  was  named  by 
Moll.  When  it  is  thought  that  the  timber  has  been 
sufficiently  impregnated  with  these  vapors,  the  surplus 
is  drawn  off,  and  vapors  from  another  still,  containing 
the  heavy  oils,  are  admitted    into    the  chamber. 


176 


SILIFICATION  OF  WOOD. 


Finally  boiling  liquid  creosote  is  introduced  into  the 
chamber  by  a  pipe,  in  a  quantity  sufficient  to  cover 
all  the  wood  therein.  It  will  be  seen  that  this  process 
is  substantially  that  of  L.  S.  Hobbins,  but  was  re- 
commended, in  1858,  by  Dr.  Krieg,  in  connection 
with  soluble  glass,  for  the  preservation  of  all  w^ood- 
work  against  fire  and  rot. — From  the  Manufmturer 
and  Builder^  Jnly^  1869. 

Wooden  Roof  Shingles. 

One  of  the  most  valuable  applications  of  the  solu- 
ble glass  may  be  recommended  for  shingles  and 
wooden  roofs  of  Farm-houses  in  the  country,  and 
near  rail  roads,  where  the  sparks  of  the  locomotives 
have  frequently  caused  deflagrations  and  destruction 
of  property. 

The  operation  is  quite  simple  and  the  expense  but 
trifling;  the  process  has  already  been  described,  but 
it  may  be  still  more  simplified  in  the  following 
manner : 

After  the  steaming  of  the  shingles  in  boilers  or  in 
tanks  where  steam  of  300  to  350^  is  led  into  them  for 
several  hours  they  are  dried  and  throwm  into  a  w^eak 
solution  of  liquid  silica,  standing  about  25 B.  from 
which  they  are  taken  out  and  exposed  to  the  air,  before 
they  are  quite  dry,  a  weak  solution  of  chloride  of  cal- 
cium is  throwm  over  them  or  sprinkled  over  them  with 
a  broom,  w^hen  quite  dry  they  are  fit  for  use.  Tliey 


SILIFICATION  OF  WOOD. 


177 


will  not  burn,  nor  be  lighted  by  the  sparks,  if 
exposed  to  a  direct  fire,  will  not  light  in  a  surround- 
ing fire.  An  intense  heat  of  long  duration  may  char 
them  on  the  surface,  they  are  however  quite  safe 
against  any  inflamation. 

Street  Pavements. 

As  a  rule,  competent  engineers  express  doubts  as 
to  the  merits  of  the  Nicolson,  and  of  wooden  pave- 
ments of  all  patterns. 

In  the  Nicolson  structure  the  road-bed  is  of  sliarp^ 
clean  sand,  of  the  pro])er  thickness.  A  basis  is  then 
made  by  laying  common  boards,  dipped  in  hot  coal-tar, 
lengthwise  on  stringers  of  like  material  laid  from 
curb  to  curb.  The  blocks  forming  the  superstructure 
are  of  Southern  hard  pine,  three  by  four,  and  are  set 
on  end  in  rows,  crosswise  of  the  street — the  blocks 
before  setting  being  dipped  to  half  their  length  in  a 
bath  of  coal-tar.  Between  the  rows  of  blocks  inter- 
vene pickets  of  thin  board  set  on  edge  and  leaving  an 
opening  between  the  rows  of  blocks,  of  a  foot  or 
nearly  in  depth.  This  opening  is  tilled  with  clean 
screened  gravel  rammed  down  with  a  paver's  ham- 
mer, and  an  iron  blade  made  for  the  purpose,  and  the 
surface  is  covered  with  hot  coal-tar.  The  gutter  ex- 
hibits its  lowest  point  half  a  foot  from  the  curb.  The 
whole  surface  is  covered  with  coal-tar  sufficiently 
boiled  to  be  tough  and  fibrous,  but  not  brittle,  upon 


178 


8ILIFICATI0N  OF  WOOD, 


which  is  sprinkled  a  layer  of  line  gravel  and  common 
sand.  The  Stafford  pavement  differs  from  the  ^»[icol- 
son  in  tlie  laying  of  large  blocks  prepared  after  the 
Seely  patent,  resting  upon  stringers,  which  in  their 
turn  may  be  supported  by  any  specified  road-bed. 
Provided  the  road-bed  is  sufficiently  secure,  say  of 
strong  concrete,  and  the  upper  deposit  is  made  suffi- 
ciently complete,  the  Stafford  pavement  cannot  but 
compare  favorably  with  other  wooden  pavements, 
and,  for  simplicity,  is  quite  superior  to  the  Nicolson. 
The  Stafford  pavement  appears  at  the  present  mo- 
ment to  be  the  favorite' one  in  the  city  of  New  York, 
as  a  large  contract  is  now  carried  out  for  the  upper 
part  of  the  city. 

Both  obviate  certain  objections  in  surface  way  which 
pertain  to  the  Belgian,  in  the  wear  and  tear  of 
vehicles  and  horses,  and  the  noise  or  reverberation  of 
wheels  ;  but  both  are  inferior  to  the  asphaltic  road  in 
these  respects,  while  the  asphaltic  has  one  great 
superiority  valuable  as  preventive  of  accident — to  wit, 
the  beating  of  the  hoof  of  the  horse  is  rendered  very 
audible — audible  above  all  other  sounds — so  as  to  be 
measurable  by  the  ear  in  the  matter  of  distance. 
This  latter  advantage  can  only  be  estimated  by  per- 
sons who  have  taken  occasion  to  note  the  extent  to 
which  one  falls  into  the  habit  of  measuring  the  dis- 
tance of  a  veliicle  from  any  given  crossing,  by  the 
ear ;  and  one  of  the  main  liabilities  to  accident,  oc- 


179  SILIFICATION  OF  WOOD. 

curring  from  wooden  pavements,  is  the  muffling  or 
comparative  muffling  of  the  hoof-beat.    In  this  re- 
spect, in  fact,  any  form  of  concrete  pavement  possesses 
material  advantages  over  either  the  stone  block, 
which  exaggerates  the  rumble  of  wheels  and  obscures 
the  hoof-beat,  or  the  wooden  pavement,  which  re- 
duces both  in  about  equal  proportions.    In  a  word,  a 
grave  objection  to  the  Nicolson  pavement  is  the  fact 
that  in  just  one  respect  it  is  a  trifle  too  noiseless  for 
the  safety  of  pedestrians  in  crossing,  especially  in 
these  days  when  every  driver  seems  to  be  possessed 
with  the  devil  to  run  over  some  body.    Again,  in  case 
of  extensive  conflagration  in  any  part  of  the  city,  the 
wooden  pavement  might  prove  a  dangerous  ally  by 
ignition,  an  instance  of  which  has  recently  occurred 
in  Philadelphia.    Neither  of  the  wooden  pavements, 
above  named  command  the  unqualified  admiration  of 
practical  engineers  as  yet,  though  the  test  of  use  is 
the  measure  of  merit  in  these  matters,  and  neither 
has  been  in  use  here  sufficiently  long  to  warrant  the 
expression  of  an  opinion. 

The  Parisian  system  has,  since  1854,  manifested 
strong  preference  for  the  asphalt  road  upon  the  con- 
crete foundation.  In  1851-,  nine  hundred  and  sixty 
square  yards  of  asphalt  road  were  laid  in  Paris,  and 
since  then  the  use  of  the  material  has  steadily  in- 
creased, until  at  present  it  is  ranked  as  well  adapted 
for  purposes  of  heavy  traffic  on  the  most  frequented 


180 


SILIFICATION  OF  WOOD. 


thoroughfares.  Up  to  1866,  96,000  square  yards  had 
been  put  down  ;  in  1867  the  surface  added  was 
54,000  in  Paris  proper,  and  84,000  in  all  in  the  de- 
partment of  the  Seine,  making  a  total  in  thirteen 
years  of  180,000  square  yards.  The  contract  of  the 
Cie  Grenerale  des  Asphaltes  with  the  city  of  Paris 
covered  at  that  date  at  least  96,000  square  yards 
more,  to  be  put  down  in  1868  and  1869.  The  ancient 
streets  of  Paris  were  without  sidewalks,  and  were 
paved  with  large  square  blocks,  with  grades  sloping 
from  the  sides  to  the  middle,  forming  a  gutter  on  the 
central  line.  Sidewalks  began  to  appear  in  1825,  and 
in  the  same  year  the  reversal  of  the  surface,  bringing 
the  gutter  to  the  sides,  was  introduced.  In  1852  the 
system  of  Mac  Ad  am  was  applied  to  the  old  boule- 
vards, and  in  1858  this  method  was  improved  for 
heavy  traffic  by  introducing  margins  along  the  sides, 
from  two  to  four  yards  in  width,  paved  with  small 
blocks  of  Belgian  porphyry — the  germ  of  the  side- 
walk as  now  used.  The  whole  surface  of  streets  and 
sidewalks  is  now  constituted  as  follows : 


SQUARB  METRES. 


Streets — paved 
Macadamized.  . 
Of  Asphalt  .  .  . 


4,833,643 
2,146,005 
165,164 


Sidewalks — of  granite 
Paved  


Total 


7,195,303 
545,939 


Bituminous 


14,024 
1,192,414 


Total 


1,752,377 


SILIFICATION  OF  WOOD. 


181 


Grand  total   8,947,679 

Equivalent  in  square  yards  to  10,701,416 

The  relative  cost  of  the  three  as  constructed  is 
worthy  of  attention,  and  may  be  added,  together  with 
the  annual  cost  of  repairs,  to  the  square  yard.  The 
generalization  exhibits  the  following  figures : 

COST  PER  SQ.  YD.  ANNUAL  REPAIR. 

Asphaltic  road   $2  50  25 

Belgian  porphyry  pavement.  . .  3  00  to  3  67  08 i  to  25 
Macadamized   1  17  42  to  50 

The  first  cost  of  asphalt  streets  is  greater  than 
that  of  macadamized,  while  the  cost  of  repairs  is 
considerably  less;  and,  again,  the  first  cost  of  the 
asphalt  is  less  than  that  of  the  Belgian  pavement, 
while  the  expense  of  repairing  is  greater.  The  as- 
phalt coating,  one  sixth  of  a  foot  thick,  is  supported 
upon  a  roadbed  of  concrete,  composed  of  ninety  parts 
gravel  to  forty  parts  of  mortar,  about  a  quarter  of  a 
foot  in  thickness,  and  rested  upon  the  comj^acted  soil 
bed  beneath.  Provided  the  requisites  of  thorough 
surface  and  imder  drainage  have  been  observed,  the 
asphalt  roofing  being  utterly  impervious  to  water, 
the  roadbed  of  concrete  waxes  harder  and  drier  with 
age,  and,  once  made,  is  imperishable.  Repairs  are 
easy,  and  consist  simply  in  cutting  away  the  damaged 
roofing  of  asphalt  and  replacing  it  with  new.  As 
compared  with  the  Belgian  pavement,  the  liability  to 
fall  of  horses  being  driven' over  tlie  asphaltic  road  is 

8 


182 


SILIFICATION  OF  WOOD. 


1  in  1409  to  1  in  1308  on  the  former,  proving  the 
Buperiority  of  the  asphaltic  surface  in  this  respect — 
that  is,  in  surety  of  foothold. 

The  concrete  known  as  heton  Coignet  differs  from 
the  ordinary  roadbed  concrete  in  being  an  artificially 
formed  sandstone  of  great  durability  and  strength^ 
and  of  extensive  application  in  civil  engineering  in 
all  its  ramifications,  from  the  manufacture  of  sewers 
to  the  construction  of  aqueducts,  from  the  fabrication 
of  roadbeds  to  that  of  underground  vaults  of  the  ut- 
most capacity.  The  best  heton  endures  a  rushing 
strength  four  and  three-fourth  times  that  of  the  best 
brick,  fifty  per  cent,  greater  than  that  of  limestone, 
fifty  per  cent,  greater  than  that  of  sandstone,  and 
about  forty  per  cent,  less  than  that  of  the  strongest 
granite,  to  thirty-five  per  cent,  more  than  that  of  the 
inferior  qualities.  For  common  use  a  good  heton  is 
compounded  of  four  parts  of  sand  and  one  part  of  fat 
lime,  to  which,  for  extra  strength,  one  half  part  of 
Portland  cement  may  be  added.  It  could  be  manu- 
factured here  at  an  expense  of  four  dollars  per  cubic 
yard,  and  for  roadbed,  a  quarter  foot  thick,  at  sixty 
cents  per  square  yard.  The  embankment  on  which 
runs  the  Avenue  de  FEmpereur,  at  the  Trocadere,  is 
supported  by  a  wall  of  this  material  forty  feet  in 
height,  for  the  distance  of  a  quarter  of  a  mile  ;  and,  in 
general,  the  subject  of  its  application  is  now  being 
discussed  and  experimented  upon  by  the  best  engineers 


SILTFICATION  OF  WOOD. 


183 


in  France,  with  a  view  to  extend  to  the  utmost  tlie 
constructive  capacity  in  engineering  of  so  inexpensive 
a  meterial  as  that  developed  by  the  invention  of  M. 
Coignet ;  while  in  the  sewerage  system  it  is  rapidly 
superseding  every  thing  else.  In  it  no  doubt  is,  at 
the  end,  to  be  sought  the  solution  of  the  sewerage 
problem  in  this  city,  if  the  administration  thereof  ever 
falls,  with  the  needed  powers  of  discretion,  into  the 
hands  of  a  competent  board  of  engineers.  What  is 
wanted  in  the  problem  is  the  boldness  to  break  loose 
from  worn  out  ideas  and  apply  the  best  invention  of 
the  age  to  the  development  of  a  better  and  more 
adequate  system — a  quality  which  lias  beenstartliiigly 
exhibited,  witli  equally  startling  and  successful  results, 
in  the  administration  of  the  Departments  of  the  Seine 
and  in  the  construction  of  public  works  in  Paris  for 
the  past  ten  years. 

Most  foreigners  travelling  in  France  remark  the 
excellence  of  the  macadamized  roads,  and  not  un- 
frequently  suppose  that  there  must  be  something 
peculiarly  favorable  in  the  nature  of  the  soil  or  some- 
thing unique  in  the  method  of  construction.  The 
supposition  is  not  true  to  fact,  however  ;  the  quality 
of  the  roads  in  France  being  attributable  to  good  en- 
gineering and  care  and  exactness  in  all  the  processes 
of  construction  and  preservation.  In  fact,  in  the 
system  of  Tresaquet  and  Simplon  the  system  intro- 
duced into  England  by  MacAdam  in  1816  had  been 


184 


SILIFICATION  OF  WOOD. 


anticipated  more  than  half  a  century.  MacAdam 
copied  Simplon  in  his  road-bed,  while  Telford  did 
nothing  more  than  return  to  the  system  founded  by 
Tresaquet  in  place  of  the  still  earlier  road-bed  of  flat 
stones.  The  roads  of  France  are  simply  illustrations 
of  what  may  be  done  by  good  construction  rather  than 
of  any  superiority  of  facilities  ;  those  of  the  city  of 
New- York  are  to  a  great  extent  examples  of  the  result 
of  slovenly  construction  with  sufficient  facilities  for 
the  best  of  work.  And  this  leads  to  the  general 
principle,  that  of  the  several  pavements  in  use  any 
one  is  practically  good  enough  for  all  purposes  when 
well  constructed.  The  defect  is  not  in  the  theory  of 
the  pavement  itself,  but  in  the  defective  and  slovenly 
application  of  it  under  the  contract  system.  As  in 
railroad-building,  with  the  result  of  innumerable 
accidents,  so  in  street-paving  defective  road-bed  is  the 
great  sin  of  the  contractor ;  and,  as  in  railroad-building, 
the  United  States  cannot  be  compared  with  France  or 
England  for  thoroughness  and  attention  to  the  details 
which  result  in  perfection,  so,  in  the  matter  of  pav- 
ement and  the  la3dng  of  it,  American  contractors  on 
the  average  are  slovenly  and  inefficient.  Contracts 
for  street-paving  are  annually  awarded  in  this  city  to 
persons  whom  a  competent  European  engineer  would 
not  trust  as  workers  under  a  superintendent ;  and  thus, 
through  ignorance  in  many  cases,  through  greed  in 
many  cases,  through  both  together  existing  in  many 


SILIFICATION    OF  WOOD. 


185 


cases,  it  is  seldom  tbat  New  York  can  boast  of  a 
section  of  pavement  properly  put  down  with  due 
attention  to  all  details.    What  is 

The  Coming  Pavement, 

or  which,  of  the  several  kinds  now  bidding  for  popular 
favor,  is  a  question  not  easily  answered.  As  a  rule, 
competent  engineers  express  doubts  as  to  the  merits 
of  the  Nicolson,  and  of  wooden  pavements  of  all 
patterns.  In  the  Nicolson  structure  the  road-bed  is 
of  sharp,  clean  sand,  of  the  proper  thickness.  A  basis 
is  then  made  by  laying  common  boards,  dipped  in  hot 
coal-tar,  lengthwise  on  stringers  of  like  material  laid 
from  curb  to  curb.  The  blocks  forming  the  super- 
structure are  of  Southern  hard  pine,  three  by  four, 
and  are  set  on  end  in  rows,  crosswise  of  the  street — 
the  blocks  before  setting  being  dii)ped  to  half  their 
length  in  a  bath  of  hot  coal-tar.  Between  the  rows 
of  blocks  intervene  ])ickets  o\»  thin  boards  set  on  edge 
and  leaving  an  opening  between  the  rows  of  blocks, 
of  a  foot  or  nearly  in  depth.  This  opening  is  filled 
with  clean  screened  gravel  rammed  down  with  a 
pavor's  rammer,  and  an  iron  blade  made  for  the  pur- 
pose, and  the  surface  is  covered  with  hot  coal-tar. 
The  gutter  exhibits  its  lowest  point  half  a  foot  from 
the  curb.  The  whole  surface  is  covered  with  coal-tar 
sufficiently  boiled  to  be  tough  and  fibrous,  but  not 
brittle,  upon  which  is  sprinkled  a  layer  of  fi^ne  gravel 


186 


SILIFICATION  OF  WOOD. 


and  common  sand.  The  Staftbrd  pavement  differs 
from  the  Kicolson  in  the  laying  of  large  blocks  prepar- 
ed after  the  Seely  patent,  resting  upon  stringers,  which 
in  their  turn  may  be  supported  by  any  specified  road- 
bed. Provided  the  road-bed  is  sufficiently  secure,  say 
of  strong  concrete,  and  the  upper  deposit  is  made  suffi- 
ciently complete,  the  Stafford  pavement  cannot  but 
compare  favorably  with  other  wooden  pavements,  and, 
for  simplicity,  is  quite  superior  to  the  Nicolson.  Both 
obviate  certain  objections  in  surface  way,  which 
pertain  to  the  Belgian,  in  the  wear  and  tear  of  vehi- 
cles and  horses,  and  the  noise  or  reverberation  of 
wheels  ;  but  both  are  inferior  to  the  asphaltic  road  in 
these  respects,  while  the  asphaltic  has  one  great  supe- 
riority valuable  as  a  preventive  of  accident — to  wit, 
the  beating  of  the  hoof  of  the  horse  is  rendered  very 
audible — audible  above  all  other  sounds — so  as  to  be 
measurable  by  the  ear  in  the  matter  of  distance. 
This  latter  advantage  can  only  be  estimated  by  per- 
sons w^lio  have  taken  occasion  to  note  the  extent  to 
which  one  falls  into  the  habit  of  measuring  the  dis- 
tance of  a  vehicle  from  any  given  crossing  by  the  ear; 
and  one  of  the  main  .liabilities  to  accident  occuring 
from  wooden  pavements  is  the  muffiing,  or  compara- 
tive muffling,  of  the  hoof-beat.  In  this  respect,  in 
fact,  any  form  of  concrete  pavement  possesses  mate- 
rial advantages  over  either  the  stone  block,  w^iicli  ex- 
aggerates the  rumble  of  wheels  and  obscures  the 


SILIFICATION  OF  WOOD. 


18T 


hoof-beat,  or  the  wooden  pavement,  which  reduces 
both  in  about  equal  proportions.  In  a  word,  a  grave 
objection  to  the  Nicolson  pavement  is  the  fact,  that  in 
just  one  respect  it  is  a  trifle  too  noiseless  for  the 
safety  of  pedestrians  in  crossing,  especially  in  these 
days  when  every  driver  seems  to  be  possessed  with 
the  devil  to  run  over  somebody.  Again,  in  case  of 
extensive  conflagration  in  any  part  of  the  city,  the 
wooden  pavement  might  prove  a  dangerous  ally  by 
ignition,  an  instance  of  which  has  recently  occurred 
in  Philadelphia.  Neither  of  the  wooden  pavements 
above  named  command  the  unqualified  admiration  of 
practical  engineers  as  yet,  though  the  test  of  use  is 
the  measure  of  merit  in  these  matters,  and  neither 
has  been  in  use  here  sufficiently  long  to  warrant  the 
expression  of  an  opinion.  In  the  great  desideratum 
of  simplicity,  as  well  as  in  the  ease  of  repair,  the  Staf- 
ford seems  to  possess  advantages  over  its  elder  in  the 
field ;  but  there  is  no  likelihood  that  either  will 
supersede  the  stone-block  to  any  great  extent.  The 
coming  pavement,  in  fact,  from  all  indications  in- 
cluded in  the  survey  of  the  subject,  is  not  to  be  found 
in  any  use  of  wooden  blocks  in  any  form  or  under 
any  conditions. 

If  the  Belgian  (stone-block)  is  ever  superceded — 
and  it  will  be  within  the  next  twenty  years — that 
supersession  will  have  been  brought  about  by  inven- 
tion, in  the  way  of  practicable  concretes.    The  as- 


188 


SILIFICATION    OF  WOOD. 


phaltic  road  in  Paris  has  given  an  impulse  to  investi- 
gation in  this  direction  which  will  not  stop  until  some 
practicable  substitute  for  the  stone-block  (Belgian) 
has  been  developed.  The  age  of  block-stone  pave- 
ments is  in  its  last  quarter — to  borrow  a  metaphor 
from  the  moon. 

The  merits  of  the  wooden  pavement  are  its  noiseless- 
ness,  its  reduction  of  the  mortality  of  horses,  its  reduc- 
tion of  the  wear  and  tear  of  vehicles,  and  its  effecting 
a  utilization  of  the  utmost  percentage  of  draught  force, 
and  these  are  all  merits  to  an  equal  degree  of  the  as- 
phaltic  road,  and  may  be  made  merits  of  any  concrete 
whatsoever.  The  increased  mortality  in  horses  occa- 
sioned by  the  Russ  and  Belgian  and  other  stone  pave- 
ments in  this  city  is  estimated  at  3,500  annually — an 
item  of  considerable  importance  in  the  discrimination 
between  pavements  for  thoroughfares.  As  between 
the  two  typical  structures,  the  Belgian  and  the  Nic- 
olson,  from  data  already  supplied,  it  may  be  estimated 
that,  with  the  attrition  of  Broadway,  the  former 
would  last  fifteen  years  against  a  last  of  half  that 
period  in  the  case  of  the  latter,  if,  indeed,  the  Nicol- 
son  can  be  regarded  as  equal  to  the  necessities  of 
Broadway  at  all.  It  is  seen,  therefore,  that  while 
the  stone  block  (Belgian  or  Russ)  is  open  to  grave 
objections  on  the  one  hand,  the  wooden  pavements- 
(Nicolson  and  Staftbrd)  are  open  to  equally  serious 
objections,  on  the  other  hand,  on  the  score  of  lessened 


SILIFICATION  OF  WOOD. 


189 


durability.  The  concrete  pavement — the  value  of 
which  has  been  happily  settled  in  Paris — elfects  a 
union  of  the  better  qualities  of  both,  without  the  ob- 
jections appertaining  to  either;  and,  as  the  minds  of 
engineers  and  inventors  are  already  beginning  to 
turn  in  this  direction,  nothing  is  hazarded  in  predict- 
ing that  the  ideal  or  coming  pavement  will  be  devel- 
oped from  the  present  crude  concretOvS.  The  asphalt 
road,  one  triumph  of  concretion,  the  hetoii  Cvignet^ 
another  triumph  in  a  direction  of  equal  ])ractical  im- 
portance, the  attempts  at  concrete  from  inexpensive 
material  in  this  country,  all  point  to  tlie  hypothesis 
that  the  solution  of  the  long-mooted  pavement  prob- 
lem is  at  hand,  in  the  evolution  of  a  concrete  roadway 
combining  the  durability  of  the  stone-block  with  the 
advantages  of  the  wooden  superstructure.  Valuable 
hints  as  to  the  constitution  of  concretes  may  be  found 
in  the  reports  of  Messrs.  Beckwith  on  heton  Coignet^ 
and  asphalt  and  bitumen  as  applied  to  the  construc- 
tion of  streets  and  sidewalks  in  Paris  ;  and,  in  the 
way  of  American  invention,  the  constitution  of  the 
Fiske  concrete  pavement,  under  the  Hairm  Burlew 
patent,  may  be  studied,  but  has  proved  so  far  a  great 
failure  in  Fifth  avenue,  where  the  concrete  had  to  be 
taken  up  again  last  winter.  This  pavement  is  com- 
posed of  gravel,  broken  stone,  cinders  and  coal  ashes 
(free  from  all  foreign  substances),  mixed  in  definite  pro- 
portions with  tar,  rosin,  and  asphaltum.    The  road- 


190  SILIFICATION  OF  WOOD. 


bed  properly  prepared,  the  composition  is  spread  on 
in  layers  of  moderate  thickness,  successively  rolled 
with  heavy  rollers  for  uniformity  and  compactness. 
These  layers  form  a  sufficiently  strong  roadway  of 
from  half  to  three-quarters  of  a  foot  in  depth,  and  can 
be  put  down  at  an  expense,  per  square  foot,  not  ex- 
ceeding the  expense  of  the  asphalt  road  as  constructed 
in  Paris.  It  remains  for  years  and  attrition  to  test 
the  practical  value  of  this  concrete ;  but,  in  general, 
it  may  be  remarked,  that  it  is  heartily  and  highly 
commended  by  thoughtful  engineers  as  a  step  in  the 
right  direction.  The  sonorousness  of  the  hoof-beat, 
as  enabling  the  pedestrian  to  measure  the  imminence 
of  passing  vehicles,  is  an  element  of  concretes  over 
wooden  pavements,  illustrated  in  an  eminent  degree 
by  the  asphaltic  road,  the  value  of  which  as  a  preven- 
tive of  accidents  cannot  be  overestimated.  A  pave- 
ment may  be  too  noiseless  as  well  as  too  noisy  for 
immunity  in  this  respect,  and  by  all  means  let  the 
capacity  of  the  concrete  be  developed  to  the  utmost. 
The  Commissioners  of  the  Park  have  also  developed 
some  excellent  roadways  in  their  admirable  system  of 
earth  roads  upon  a  similar  principle  ;  though  in  rela- 
tion to  the  Park,  the  problem  has  been  less  difficult 
of  solution,  no  necessity  existing  to  provide  for  the 
contingency  of  heavy  traffic.  In  its  capacity  for  the 
combination  of  all  the  qualities  which  experience 
has  proved  to  be  desirable  in  a  roadway  for  large 


SILIFICATIOX  OF  WOOD.  191 

cities,  the  concrete  must  therefore  be  ranked  as  supe- 
rior to  either  of  its  competitors,  with  some  most  im- 
portant and  indispensable  improvements  to  be  applied, 
and  as  embodying  in  itself  the  germ  of  the  coming 
pavement  in  this  city,  and  the  suggested  reforms  in 
the  sewarage  system  having  been  carried  out,  atten- 
tion may  be  directed  to  the  production  of  an  inexpen- 
sive concrete,  analogous  to  the  asphaltic  road. 

Discussion  on  the  subject  as  it  relates  to  the  city 
would  be  incomplete  without  due  consideration  of 
the 

Typical  Historical  Pavement, 

based  upon  the  Roman  system,  and  its  susceptibility 
for  improvement ;  for  it  is  a  fact  that  a  large 'class  of 
conservative  engineers  still  look  for  the  advent  of  the 
ideal  pave  in  some  modification  of  the  stone- 
block  on  the  concrete  road-bed.  The  completion, 
during  the  past  week,  of  the  relay  of  the  Broadway 
pave,  at  an  expense  of  nearly  8500,000,  recalls  the 
fact  that  no  question  exists  as  to  the  vulue  of  the  sub- 
structure of  concrete.  The  question  is  as  to  super- 
structure. Large  stone  blocks  on  a  road-bed  of  sand 
form  the  major  part  of  the  pavement  of  the  city — the 
large  block  pave  being  less  expensive  than  the  small. 
On  Broadway  the  unique  feature  introduced  consists 
in  splitting  the  blocks  by  a  lateral  fissure,  leaving 
them  in  point  of  superficial  appearance  parallelo- 


192  SILIFICATION  OF  WOOD. 

grams  a  quarter  of  a  foot  in  width,  against  a  foot  or 
thereabouts  in  length.  This,  by  quadrupling  the 
number  of  joints,  affords  a  sure  foothold  for  horses, 
especially  as  the  blocks  are  laid  traversely — the  line 
of  travel  crossing  the  linear  of  the  nave  and  surface 
at  right  angles  with  the  length,  with  the  effect  to 
afford  an  average  of  four  clinging  points  for  the 
horseshoe  in  the  new  pave  to  one  in  the  old.  This 
decreases  the  liability  to  slip,  really  dividing  it  by 
four,  and,  with  the  concrete  bed,  fulfils  the  ideal  of 
the  old  Roman  pave.  The  want  of  elasticity  is,  how- 
ever, in  nowise  obviated ;  the  difficulty  of  traction  ia 
by  no  means  lessened,  the  jar  and  volume  of  sound 
are  not  in  the  leastwise  substracted  from.  The  sani- 
tary purpose  is  met,  and  percolation  is  prevented ; 
but  no  part  of  the  $10,000,000  annual  wxar  and  tear 
of  horses  and  vehicles  is  saved;  and  this  is  a  matter 
to  be  considered  in  the  pavement  of  a  city.  The  im- 
portant question  is  to  settle  upon  the  desiratum  in 
the  way  of  superstructure.  The  true  method  of  in- 
vention would  seem  to  be  to  make  beton  Coignet  the 
basis,  and  to  this  to  superadd  some  fourth  ingredient 
to  develop  the  needed  elasticity,  which  may  be 
effected  by  the  addition  of  the  liquid  silicates.  Tar 
boiled  to  the  point  of  elastic  solidity,  or  asphaltum, 
which  can  be  procured  at  twenty  dollars  per  ton, 
currency,  might  be  added  in  small  proportions  to  the 
heton ;  and  in  this  way,  by  experiment,  a  concrete 


8ILIFICATION  OF  WOOD. 


193 


might  be  developed  equal  in  all  respects  to  the  as- 
phaltic  road,  now  so  popular  with  the  engineers  in 
Paris.  The  hugh  quarries  of  trap  along  the  East 
River  render  the  Russ  pavement  tolerably  inexpen- 
sive ;  and  hence,  in  order  practically  to  supercede  it^ 
something  must  be  produced  which  can  be  put  at 
$2.50  or  less  per  square  yard,  and  as  durable  as  the 
block-stone.  An  able  and  competent  engineer  esti- 
mates the  loss  in  horses,  extra  wear  of  vehicles  and 
extra  horseshoeing  in  the  cities  of  the  United  States, 
occasioned  by  block-stone  and  cobble-stone  pave- 
ments, at — 

On  horses  $15,000,000 

On  vehicles   20,000,000 

On  horseshoing   21,000,000 

Total  $56,000,000 

The  province  of  invention  in  respect  to  pavements, 
is  to  save  this  vast  amount  by  the  substitution  of  a 
concrete  upper  structure  as  inexpensive  and  durable 
as  the  Belgian,  and  as  elastic  and  easy  as  the  wooden, 
which  has  failed  in  the  respect  of  durability  as  well 
as  over-expensiveness,  and  can  never  be  generally 
adopted . 

Most  roadway  surfaces,  it  is  clear,  should  afford,  in 
the  first  place,  certain  and  firm  foothold  for  horses ; 
secondly,  as  little  resistance  to  wheels  as  possible ; 
thirdly,  permanence,  as  regards  structure  and  firm- 


194 


8ILIFICATI0N  OF  WOOD. 


Tiess  ;  fourthly,  such  qualities  as  will  ensure  ease  iti 
draining  and  cleaning;  and  fifthly,  facility  for  re- 
moval and  replacement.  There  can  be  no  difference 
of  opinion  about  these  conditions.  No  matter  how 
thoroughly  excellent  a  pavement  may  be  otherwise, 
if  it  only  affords  a  slippery  and  unstable  footing  for 
horses,  it  is  worthless,  and  its  perfection  in  other 
points  wasted.  The  greater  the  amount  of  strength 
the  horse  has  to  exert  the  more  increased  is  his  lia- 
bility to  slip.  This  arises  from  the  fact  that  his  hoof 
always  strikes  the  pavement  toe  first,  the  point  of 
contact  then  becoming  the  fulcrum  about  which  his 
leg  moves  as  a  lever,  so  that  the  greater  the  load  the 
greater  the  pressure  on  this  fulcrum,  with  resulting 
increased  tendency  to  slip.  Hence,  no  pavement  is 
at  all  perfect  which  presents  a  smooth,  hard,  un- 
broken surface,  or  that  has  any  great  longitudinal  or 
transverse  slope.  A  pavement,  to  offer  as  little  resist- 
ance to  wheels  as  possible,  must  have  great  hardness, 
smoothness,  evenness,  and  no  elasticity.  As  to  per- 
manence as  regards  surface  and  structure,  any  pave- 
ment requiring  frequent  renewals  is  an  expensive 
one,  no  matter  how  small  its  original  cost.  True 
economy  will  allow  a  most  liberal  original  outlay  for 
a  pavement  which,  if  satisfactory  in  other  respects, 
aflbrds  permanence.  The  cost  of  frequent  renewals 
and  repairs  is  not  only  a  large  item  of  direct  expense^ 
but  while   the  pavement  is  settling  and  wearing 


8ILIFICATION  OF  WOOD. 


195 


smooth  the  draught  and  the  wear  and  tear  of  vehicles 
are  increased,  and  the  necessary  blocking  up  of  the 
roadway  while  the  repairs  of  construction  are  actu- 
ally in  progress,  causes  delay  and  time-consuming 
detours,  unavoidably  crowding  the  adjacent  streets, 
while  greatly  inconveniencing  warehouse  owners  by 
preventing  the  delivery  and  loading  of  goods  imme- 
diately at  the  warehouses.  To  secure  permanence 
we  must  consider  locality,  material,  construction  and 
surface.  As  to  the  locality,  it  is  essential  to  examine 
the  nature  of  its  traffic  and  transportation,  the  nature 
of  the  soil  on  which  the  pavement  must  rest,  and  the 
climate  to  which  it  will  be  exposed.  The  nature  of 
the  traffic  should  be  specially  studied,  as  it  would  be 
manifestly  injudicious  and  wasteful  to  place  a  stone 
block  or  iron  pavement  on  the  roads  of  pleasure 
grounds,  or,  ince  versa^  to  transfer  a  park  gravel  road 
to  a  crowded  business  street.  We  should  note  the 
character  of  the  soil,  whether  it  be  properly  drained 
by  nature  or  artificially ;  whether  it  is  composed  of 
homogeneous,  dry  and  incompressible  material,  like 
sand,  or  is  soft  and  spongy,  as  it  invariably  is  when 
the  street  has  been  much  used  without  pavement,  or 
has  been  filled  in  with  building  or  street  rubbish. 
The  climate  of  the  locality  must  be  considered,  as 
some  pavements  lasting  well  under  certain  conditions 
of  moisture  and  temperature  become  speedily  perish- 
able when  these  conditions  are  changed.    This,  per- 


196 


SILIFICATION  OF  WOOD. 


haps,  is  particularly  noticeable  in  the  use  of  wooden 
or  macadamized  pavements.  Pavement  material 
should  be  thoroughly  examined  with  regard  to  it& 
tendency  to  decay  and  disintegration,  to  tearing  to 
pieces  or  grinding  up.  With  regard  to  construction, 
we  must  separately  look  to  the  foundation  and  the 
upper  part,  or  pavement  proper.  Without  proper 
foundation  or  bed  no  pavement  can  attain  much 
longevity.  It  must  be  thoroughly  dry,  rigid  or  in- 
compressible, and  when,  uniformly  thick  pavement 
blocks  are  used,  even-surfaced.  A  clean  pavement  is 
not  only  healthy  and  sightly,  but  economical.  The 
pavement  surface  should  be  so  graded  as  to  clean  it- 
self to  a  great  extent  during  every  rain-fall.  This 
may  be  most  efficiently  accomplished  by  the  longitu- 
dinal slope  of  the  street,  very  slight  lateral  slopes 
being  needed. 

Yarious  Systems  Adopted  for  Broadway  Pave- 
ments. 

A  great  variety  of  systems  have  been  adopted  for 
roadway  pavements.  The  most  convenient  classifi- 
cation of  them  is  into  gravel  compositions,  broken 
stone,  plank,  wooden  block,  cobble  stone  or  pebble 
stone  block  and  iron  block  pavements  and  tramways. 
The  first  attempts  at  pavements  generally  com- 
mence with  the  use  of  gravel.  Roads  thus  made 
possess  the  advantages  of  cheapness  of  material  and 


SILIFTCATION  OF  WOOD. 


construction.  In  the  Park,  where  there  are  probably 
the  most  perfect  roads  in  this  country,  they  have 
shown  better  endurance  than  those  made  on  the  mac- 
adam plan.  Gravel  roads,  when  properly  constructed 
and  maintained,  are  comparatively  smooth  and  noise- 
less, besides  aftbrding  excellent  foothold  for  horses. 
The  great  objections  to  them  are  that  they  cannot  he 
kept  firm  enough  to  afford  easy  draugiit  for  heavy 
traffic  ;  that  they  lack,  in  a  high  degree,  permanence^ 
and  are  constantly  requiring-  repairs ;  that  they  are 
difficult  to  keep  clean  and  to  drain  properly ;  the 
rapidly  grinding  and  crusliing  to  powder  tending 
greatly  to  cause  dust  in  dry  weather  and  mud  in  wet 
weather ;  and,  lastly,  that  the  best  construction  yet 
attained  has  failed  to  prevent  tliem  from  Avasliing 
into  gullies.  Under  the  head  of  second  composition 
pavements  may  properly  be  included  pavements 
formed  by  the  combinations  of  several  materials,  such 
as  the  famous  asplialt  pavement  of  Paris,  concrete, 
heton^  gutta  percha,  slag,  cinder,  and  other  pave- 
ments ;  also,  those  formed  according  to  the  experi- 
ments of  McNeil,  partly  of  broken  stone  and  partly 
of  pieces  of  cast  metal,  laid  on  a  sub-pavement  of 
rubble  stone.  The  asphalt  pavement  of  Paris,  so 
often  recommended  in  newspaper  articles,  is  really 
quite  an  imperfect  pavement.  It  is  generally  formed 
on  a  foundation  of  macadamized  road.  Powdered 
asphalt  is  placed  on  the  foundation  and  stamped  with 


198 


SILIFICATION  OF  WOOD. 


hot  rammers  until  it  is  very  hard  and  has  a  thickness 
of  one  or  two  inches.  It  is  very  pleasant  and  smooth 
to  ride  over,  but  requires  most  constant  watching  and 
repairing.  It  is  slippery  in  wet  weather,  and  exces- 
sively so  at  a  freezing  temperature. 

Pavements  of  Granite. 

Granite  blocks,  considered  in  every  respect,  form 
one  of  the  most  perfect  pavements  known.  They  are 
preferred,  and  almost  exclusively  adopted,  in  Lon- 
-don.  The  Russ  pavement,  the  nearest  approach  to 
-SL  perfect  pavement  yet  constructed  in  this  city,  has, 
in  imitation  of  the  Horn  an  pavement,  a  heto?i  founda- 
tion of  six  inches  thick.  The  heton  is  composed  of 
one  part  cement  to  two  and  a  half  parts  of  broken 
stone  and  two  parts  of  gravel.  On  this  foundation 
^re  laid  hard  granite  blocks  ten  inches  deep,  ten  to 
■eighteen  inches  long,  and  from  five  to  twelve  inches 
wide.  It  is  very  durable,  and  yet,  as  shown  in  Broad- 
way, this  excellent  pavement  has  most  signally 
failed,  the  surface  of  the  granite  used  polishing  and 
affording  dangerous  foothold.  What  is  required,  and 
this  would  give  a  perfect  pavement,  is  the  adoption 
of  the  kind  of  stone  blocks  used  in  London,  which  do 
not  polish  by  wear,  and  present  joints  about  every 
four  inches.  Another  pavement  is  now  being  substi- 
tuted here  in  an  imperfect  manner.  The  blocks  now 
used  are  of  a  coarser  granite,  twelve  inches  long,  nine 


SILIFICATION  OF  WOOD. 


199 


inches  deep,  and  four  inches  wide,  the  courses  run- 
ning at  right  angles  with  the  line  of  the  street.  What 
is  known  as  the  Belgian  pavement  was,  until  recently, 
the  principal  one  in  use  in  the  old  streets  of  Paris, 
and,  as  is  well  known,  has  been  quite  extensively 
adopted  in  this  city.  This  pavement  has  the  advan- 
tage of  cheapness,  and,  if  well  laid,  of  economy,  the 
necessary  and  actual  cost  being  a  little  over  one- 
half  that  of  the  Nicolson  pavement.  The  final 
trouble,  however,  is  their  becoming  polished  and 
slippery,  and  hence  they  should  not  be  laid  in  streets 
where  they  are  subject  to  constant  use. 

Ikon  Block  Pavements. 

Several  attempts  have  been  made,  with  more  or 
less  success,  to  cast  iron  in  blocks  suitable  for  pave- 
ments. The  chief  objection  is  the  cost  of  iron,  but  if 
properly  laid  there  can  be  no  doubt  of  its  being 
cheaper  in  the  end  than  most  other  pavements.  It 
has  failed  hore  on  account  of  its  inadequate  and  de- 
fective foundation,  and  on  account  of  the  principle 
employed  of  keying.  The  rings  pressing  on  the  sand 
foundation  gave  too  little  bearing  surface,  and  any 
weight  tended  greatly  to  displace  or  overturn  the 
block,  which  occurring,  all  the  neighboring  ones  key- 
ing into  it  were  released,  and  unless  quickly  repaired, 
the  ruin  of  the  whole  pavement  soon  followed.  It 
has  stood  much  better  in  Boston,  and  for  the  simple 


200 


SILIFICATION   OF  WOOD. 


reason  of  its  being  better  laid.  It  has  stood  there 
admirably,  and  shows  no  material  signs  of  surface 
wear  after  ten  or  twelve  years  of  constant  use.  It 
can  be  cast  in  such  form  as  to  give  the  best  foothold 
for  horses  drawing  heavy  loads.  It  can  be  kept  per- 
fectly even  and  made  smooth  as  the  l^icolson  pave- 
ment, and  by  its  extreme  hardness  will  give  much 
less  resistance  to  wheels.  Being  of  uniform  quality, 
all  parto  will  wear  equally^  and  as  perfect  a  ftice  will 
always  be  presented  as  when  new.  Its  smoothness 
tends  greatly  to  lessen  the  noise,  as  this  nuisance  is 
caused  principally  by  the  boxes  of  the  wheels 
striking  against  the  collars  on  the  axles,  and  of 
course  increases  with  roughness  of  pavement  surface. 
Iron,  furthermore,  loses  but  little  from  oxidation.  It 
can  be  kept  as  clean  as  the  Nicolson  pavement,  with 
the  advantage  of  non-absorption.  It  has  one  great 
advantage  in  being  made  so  as  to  be  easily  and  readily 
removed  and  repla(;ed,  the  blocks  formed  from  the 
same  pattern,  being  exact  counterparts. 

The  Fisk  Concrete  Pavement. 

This  pavement  is  composed  of  seventy  per  cent,  in 
bulk  of  broken  stone,  coal  or  gravel,  clean  coal  or 
iron  cinders  not  over  three  inches  in  any  dimensions. 
These  are  passed  over  a  screen  with  meshes  one  quar- 
ter inch  square.  The  coarser  portion  is  then  coated 
by  mixing  with  tar,  warm  or  cold,  and  then  spread 


SILIFICATION  OF  WOOD. 


201 


on  the  roadbed  and  heavily  rolled  until  a  depth  of 
four  inches  is  attained.  The  finer  portion  is  then 
mixed  with  clean  sharp  sand,  warmed,  and  then  thor- 
oughly mixed  with  tar,  to  which  has  been  added 
rosin,  carbojapanis  or  pitch.  This  is  placed  on  the 
first  layer  of  coarse  material  and  rolled  until  a  depth 
or  two  inches  is  attained,  after  which  the  surface  is 
covered  with  an  excess  of  clean  sharp  sand  and  again 
rolled. 

The  Nicolson  Pavement. 

We  now  come  to  the  subject  of  wooden  pavements. 
The  first  general  attempt  to  use  wooden  blocks  for 
pavements  took  place  some  thirty  years  ago  both  in 
this  country  and  Europe.  They  are  generally  made 
in  the  form  of  hexagonal  prisms  of  hard  wood,  laid 
directly  on  sand  or  earth.  Leading  oft'  in  the  list  of 
wooden  pavements  adopted  in  this  city  is  the  Nicolson 
pavement.  In  laying  this  pavement,  the  street  is 
first  prepared  by  a  sufficient  covering  of  sand,  which 
is  brought  to  the  proper  crown  with  a  straight  edge 
made  for  that  purpose.  This  surface  is  then  covered 
with  common  round  inch  boards,  laid  lengthwise 
with  the  line  of  the  street.  The  ends  of  these  boards 
rest  on  stringers  of  the  same  material  laid  from  curb 
to  curb. 

Both  sides  of  these  boards  are  covered  with  hot  coal 
tar.    The  blocks  are  of  Southern  pine,  three  inches 


202 


SILIFICATION  OF  WOOD. 


wide  and  six  inches  deep,  and  are  set  on  end  in  rows 
crosswise  of  the  street.  Before  setting,  the  blocks 
are  dipped  to  half  their  height  in  hot  coal  tar.  Be- 
tween each  row  of  blocks,  and  at  their  base,  pickets 
one  inch  thick  and  three  inches  wide  are  nailed  on 
edge.  The  opening  thus  formed  between  the  rows  is 
filled  with  clean  screened  gravel  rammed  with  a 
payor's  rammer  an  iron  blade  made  for  that  purpose, 
and  then  covered  with  hot  coal  tar.  The  whole  of 
the  upper  surface  of  the  pavement,  when  laid,  is 
covered  with  hot  coal  tar,  boiled  to  a  consistency, 
which,  when  cold,  is  to  be  tough,  fibrous  and  not 
brittle,  and  then  covered  with  fine  gravel  and  com- 
mon sand.  After  the  top  gravel  has  become  packed 
on  the  surface  and  in  the  grooves,  the  street  is  swept. 

The  M'Gonegal  Pavement. 

This  pavement,  claimed  to  be  an  improvement  on 
the  Nicolson,  to  which  it  is  similar,  consists  of  a 
foundation  of  two  inches  of  heton^  on  which  are 
placed  wooden  blocks  six  inches  deep,  two  and  three- 
quarter  inches  wide,  and  from  four  to  sixteen  inches 
in  length.  Holes  of  one  and  a  half  inches  in  diame- 
ter, and  three  and  a  half  inches  deep,  are  bored  in 
each  block,  and  then  triangular  grooves  formed  on 
each  side  of  the  blocks,  so  that  when  two  blocks  are 
placed  together,  there  will  be  a  square  opening  one 
and  a  quarter  inch  square  to  receive  a  wooden  dowel 


SILIFICATION  OF  WOOD.  203 

or  key.  The  wood  used  for  blocks  and  keys  is  pre- 
pared for  preservation  by  Bobbins'  process.  In  lay- 
ing, the  blocks  and  keys  are  dipped  in  hot  coal  tar. 
The  perforations  in  the  blocks  are  filled  with  clean 
roofing  sand.  The  pavement  is  finished  by  a  coating 
three-quarters  of  an  inch  in  thickness  of  coal  tar  and 
fine  sand.  These  are  the  specifications  as  we  have 
described  them ;  but  where  this  pavement  lias  been 
laid  in  this  city,  a  foundation  of  flooring  of  tarred 
boards  has  been  substituted  for  that  of  heton. 

The  Stowe  Pavement. 

In  constructing  this  pavement,  which  is  also 
wooden,  and  a  cheap  form  of  the  Nicolson,  the  street 
is  first  filled  with  sand,  loam  or  loose  earth,  free  from 
stones,  to  within  about  six  Inches  of  the  desired 
street  grade,  but  smoothed  off  so  as  to  conform 
to  the  desired  arch  or  crown  of  the  street ;  then 
blocks  of  sound  pine  or  spruce  wood  three  inches  in 
thickness,  and  six  inches  iu  length,  are  set  on  their 
ends  in  a  tier  across  the  street,  these  blocks  being  cut 
square  at  both  ends.  A  tier  of  blocks  made  wedge- 
shape  at  their  ends  by  beveling  on  one  side  is  set 
across  the  street  close  against  the  first  tier  of  square- 
ended  blocks,  which  are  set  up  as  before,  and  so  on 
alternate  tiers  of  square  and  wedge-shaped  blocks  are 
placed  until  a  space  of  ten  feet  or  more  is  covered, 
then  the  wedge-shaped  blocks  are  driven  down  into 


204 


SILIFICATION  OF  WOOD. 


the  sand  or  earth  with  rammer  and  swage  until  tlie 
foundation  is  of  the  required  compactness.  The  cells 
or  spaces  between  the  three-inch  blocks  are  filled 
with  clean  coarse  gravel,  not  exceeding  three-fourths 
of  an  inch  in  diameter,  thoroughly  driven  with  ram- 
mer and  swage,  then  the  gravel  saturated  with  hot 
€oal  tar,  and  the  whole  surface  covered  with  hot  coal 
tar,  and  lastly,  the  pavement  covered  with  fine  gravel 
or  sand. 

The  Brown  and  Miller  Pavement. 

This  pavement  is  also  similar  to  the  Nicolson,  only 
that  its  blocks  are  not  set  vertically,  but  at  an  angle 
of  forty-five  degrees,  and  rest  on  sills  of  a  prismatic 
form,  which,  in  turn,  rest  on  boards  placed  five  feet 
apart  and  parallel  with  the  line  of  the  street. 

The  Robbins'  Pavement. 

This  is  another  of  the  multifarious  wooden  pave- 
ments recently  introduced  in  this  city.  It  is  very 
similar  to  the  Nicolson,  only  the  wood  used  is  first 
prepared  by  Pobbins'  patent  wood  preserving  pro- 
cess. 

The  Stafford  Pavement 

is  only  another  imitation  of  the  great  original  Nicol- 
son.  The  blocks  are  dressed  to  a  uniform  thickness, 
grooved  in  the  middle  with  a  double  dovetail,  two 


SILICIFICATION  OF  WOOD. 


205 


and  one-half  bj  three-fourtli  inches,  each  side  of  the 
block  bevelled  at  one  end,  and  running  to  an  edge  so 
as  to  form  a  groove  on  the  upper  surface. 

Seeley's  Concrete  Pavement 

now  being  put  down  in  Eleventh  street,  near  Univer- 
sity place,  consists  of  sulphur,  three  parts ;  gas  tar, 
twelve  parts ;  silica  (pebbles)  sixty  parts,  by  weight. 
The  pebbles  are  heated  230^  Fahrenheit  before  being 
mixed  with  the  melted  sulphur  and  tar. 

WOODEN  pavements,  VeVSUS  STONE  AND  CEMENT. 

The  failure  of  the  concrete  in  Fifth  Avenue  for 
which  the  citizens  were  mulcted  in  the  sum  of  half  a 
million  of  dollars,  and  which  was  taken  up  during 
the  winter  on  account  of  its  uselessness.  The  various 
stone  pavements,  which  have  from  time  to  time  been 
brought  forward  by  the  patentees  and  speculating 
companies,  have  all  brought  the  unbiased  and  practi- 
cal men  to  the  conclusion  that  for  comfort  a  wooden 
pavement  in  such  streets  as  Fifth  Avenue,  would 
prove  by  far  preferable  to  any  other,  provided  it  is 
made  durable,  at  the  same  time  a  proper  concrete  as 
mentioned  in  these  pages  in  connection  with  silicates 
may  with  great  propriety  be  employed  as  a  base  but 
not  as  a  capping  for  either  stone  or  wooden  pave- 
ment ;  whether  this  shall  be  a  concrete  or  whether 
the  base  shall  be  of  planks  properly  prepared  and 

9 


206 


SILICinCATION  OF  WOOD. 


Bilicitied  so  as  to  construct  the  blocks  upon  it,  is  a 
matter  of  great  importance,  and  is  well  worth  a  re- 
flection and  experiment  upon  a  small  scale,  but  not 
hazarding  an  outlay  of  perhaps  a  million  of  dollars, 
and  the  experiment  to  prove  again  a  failure. 

The  following  method  of  application  is  recommen- 
ded by  the  author : 

The  planks  and  wooden  blocks,  intended  as  pave- 
ment, the  size  of  the  planks  being  from  10  to  12  feet 
in  length  and  1  inch  in  thickness,  and  the  blocks 
from  10  to  12  inches  square  and  in  the  first  place  ex- 
posed the  iron  boilers  to  a  temperature  of  300^  F.  for 
several  hours,  or  kept  for  4-6  hours  in  boiling  water, 
containing  2  per  cent,  of  soda  ash,  which  possesses 
the  property  of  dissolving  the  albumen  and  sap  con- 
tained in  the  cells  of  the  wood  and  by  the  boiling  the 
coloring  matter  is  extracted  from  the  wood;  when 
taken  from  the  boilers,  they  are  brought  in  drying 
chambers  of  high  temperature,  and  then  removed  to 
vats  containing  crude  carbolic  acid  and  tar  water 
standing  for  6-8^  B.  which  will  enter  into  the  pores, 
left  open  by  the  previous  process  and  a  large  portion 
of  the  liquid  will  be  absorbed ;  from  thence  they  are 
thrown  in  vats  containing  hot  silicate  of  soda,  stand- 
ing 20 B.  and  left  therein  for  4-6  hours ;  they  are 
then  removed  and  dried  either  in  air  or  hot  chambers. 
When  perfectly  dry  they  are  suitable  for  being  put 
on  a  smooth  ground,  which  may  consist  of  a  cement 


SILICIFICATION  OF  WOOD. 


20T 


of  silicated  hydraulic  lime  or  cement.  The  interstices 
of  the  ends  of  the  blocks  may  likewise  be  made  tight 
by  applying  a  silica  cement  between  each. 

The  Mode  of  Application. 

The  frequent  enquiries  how  to  apply  the  soluble 
glass,  and  how  much  is  required  for  spreading  over 
certain  surfaces,  may  herewith  be  recommended  in  the 
following  manner ;  application  for  hardening  stones  as 
a  mortar  between  bricks,  or  any  cement  or  composi- 
tion for  wall,  cistern,  cellar,  or  roofing. 

In  all  cases  the  liquid  soluble  glass,  either  the 
silicate  of  soda  or  potash,  or  both  combined,  are 
diluted  with  equal  quantities  of  water  so  as  to  stand 
25'^  B,  If  strong  cements,  or  lutes,  where  various 
other  substances  along  with  the  dry  silicate  and 
metallic  oxides  are  to  be  employed,  the  soluble  glass 
is  not  diluted  but  employed  from  30-35*^  B,  suffi- 
ciently to  make  a  plastic  composition ;  but  where 
it  is  intended  for  mending  or  filling  cracks  or  holes 
either  in  stoves  or  iron  castings,  discretion  of  the 
consistency  of  the  mass  must  be  used,  as  it  may  be 
more  advantageous  for  the  cement  to  dry  slowly,  so 
as  to  prevent  too  sudden  a  contraction. 

For  painting  or  coating  on  stone,  it  is  useful  to 
apply  the  dilute  by  a  syringe,  and  if  necessary,  re- 
peat tlie  operation  2-3  times  after  each  drying.  For 
preserving  monuments,  tombstones,  marble  columns, 


208 


SILICIFICATION  OF  WOOD. 


etc.,  the  dilute  silicate  of  soda  may  be  used  as  a 
wash  with  or  without  the  addition  of  baryta  (the 
precipitated  sulphate  of  baryta  is  always  preferred 
although  expensive),  lead,  zinc,  or  limewash,  by 
means  of  a  paint  brush  and  according  to  the  con- 
dition of  the  stone  as  to  porosity.  If  the  chloride 
of  calcium,  chloride  of  iron,  or  dilute  hydrofluoric 
acid  are  applied  upon  the  surface  of  the  stone, 
cement  or  paint,  they  are  thrown  over  the  silicated 
surface  uniformly,  so  as  to  cover  every  part  of  the 
material  to  be  treated.  In  all  cases  it  is  understood 
that  the  silicate  application  is  to  be  applied  on  new 
stone,  for  it  will  not  adhere  on  old  paint ;  therefore, 
if  it  is  to  be  used,  it  is  indispensible  that  it 
be  first  removed  by  soap,  caustic  alkali,  spirits  of 
turpentine,  or  even  acids,  and  when  perfectly  clean 
and  dry,  the  operation  of  silicating  may  take  place. 
In  all  cases  where  the  substances  are  to  be  painted 
or  undergo  a  silification,  it  may  be  repeated  2-3  times 
at  each  interval  of  at  least  12  hours  ;  a  weak  hydro- 
fluoric acid  may  in  all  cases  be  used  as  a  wash  over 
the  silicated  stones;  1,000  square  feet  of  wall  cover- 
ing can  be  executed  with  200  gallons  of  dilute  silicate 
of  either  soda  or  potash.  In  diluting  the  silicate,  it 
is  well  to  employ  3  applications  of  various  quali- 
ties, such  as  for  instance,  the  flrst  coat  may  consist  of 
part  of  silica  to  2  parts  of  water,  and  another  of 
equal  quantities  of  water,  and  the  last  coat  the  dilu- 
tion to  be  1  part  of  water. 


SILICIFICATION  OF  WOOD. 


209 


Wood  and  timber  of  every  description  may  be 
treated  witb  the  concentrated  silicates. 

For  Preservation  of  Walls. 

It  is  well  known  that  brick  absorbs  its  weight  of 
moisture  and  requires  much  attention.  The  external 
surfaces  of  the  walls  to  be  protected  are  first  washed 
with  a  silicate  of  soda,  which  is  applied  again  and 
again,  until  the  bricks  are  saturated,  and  the  silicate 
ceases  to  be  absorbed.  The  strength  of  the  solution  is 
regulated  by  the  character  of  the  bricks  upon  which  it 
is  to  be  applied,  a  heavier  mixture  being  used  upon 
porous  walls,  and  a  lighter  one  on  those  of  denser 
texture.  After  the  silicate  has  become  thoroughly  ab- 
sorbed,and  none  is  visible  upon  the  surface,  a  solution 
of  chloride  of  calcium  is  applied,  which,  immediately 
combining  with  the  silicate  of  soda,  forms  a  perfectly 
insoluble  compound,  which  completely  fills  up  all  the 
interstices  in  the  brick  or  stone,  without  in  any  way 
altering  its  original  appearance.  By  this  operation 
the  wall  is  rendered  perfectly  watertight,  and,  as  the 
pores  of  the  bricks  are  thoroughly  filled  for  a  consi- 
derable depth  from  the  surface  with  the  insoluble 
compound,  which  is  entirely  unaffected  by  atmos- 
pheric influences,  no  subsequent  process  is  necessary. 


^10 


SILIOIFICATION  OF  WOOD. 


The  Protection  of  Rail  Eoad  Sleepers,  Cross 
Ties,  Frame  Houses,  Telegraph  Poles,  Timber, 
Staves,  Shingles,  Laths,  Tanks,  Tubs,  Casks, 
Barrels  (Petroleum,  Kaptha,  Spirits  Turpen- 
tine, Alcohol,  Linseed  Oil),  Cisterns,  and 
Every  Description  of  Wood,  against  Fire, 
Dry  Rot  and  Leakage. 

The  seasoning  or  initiatory  preparation  of  the  lum- 
ber, so  as  to  destroy  the  organic  or  nitrogenized  mat- 
ters enclosed  in  all  the  cells  of  vegetable  matters,  are 
dissolved  and  washed  out  of  it,  or,  in  other  words, 
the  removal  of  all  the  albumen,  sap  and  coloring 
matter,  is  effected  by  exposing  for  from  four  to  six 
hours  to  boiling  water,  containing  about  one  per 
cent,  of  soda  ash  in  solution.  They  are  then  with- 
drawn and  dried  in  hot  rooms,  and  then  thrown  into 
tanks  containing  the  tar  and  carbolic  acid  water,  and 
left  for  a  few  hours,  then  dried  again  and  thrown  into 
a  hot  solution  of  silicate  of  soda  standing  20®  B.,  in 
which  they  are  left  for  ten  or  twelve  hours.  When 
removed  from  here  a  weak  limewash  is  applied  with 
a  brush  or  sponge,  consisting  of  10  lbs.  slacked  lime 
to  40  gallons  of  water,  when  likewise  they  are  re- 
moved to  a  dry  or  hot  air ;  after  that  a  weak  wash  of 
chloride  of  calcium  is  thrown  or  brushed  over  them 
when  nearly  dry.  The  process  is  then  finished,  and 
the  articles  so  prepared  will  resist  the  elements  aa 


SILICIFICATION  OF  WOOD. 


211 


above  stated.  They  increase  in  weight  by  this  pro- 
cess about  6  per  cent.  After  this  treatment,  they 
assume  upon  the  first  drying  a  glazed  appearance, 
and  the  pores  are  filled  with  insoluble  silicas  precipi- 
tated by  the  action  of  the  tar  liquor  upon  the  alkali 
of  the  silicate  of  soda.  Barrels  which  have  been 
treated  may  be  rendered  perfectly  impervious  by  fill- 
ing up  the  chimes  (the  inside  of  those  barrels  having 
been  treated  with  the  silicate  of  soda  and  chloride 
calcium)  with  a  thin  silicated  cement  applied  on  the 
interstices.  No  air  nor  any  liquid  will  then  have 
any  eftect ;  the  lightest  liquid  may  then  be  kept  in 
those  prepared  barrels  without  escaping — flour,  but- 
ter, lard,  and  many  other  perishable  substances  may 
be  kept  for  a  length  of  time  in  barrels  so  prepared. 
Spirits  of  turpentine,  linseed  oil,  alcohol,  and  other 
'  spirituous  liquors  may  safely  be  transported  and  kept 
for  a  length  of  time  without  evaporation  or  loss  in 
the  contents  of  the  barrels.  Telegraph  ])oles^  which 
are  from  twenty  to  thirty  feet  long,  require  a  difter- 
ent  treatment  for  their  seasoning  before  they  undergo 
the  silification.  They  are  steeped  first  in  the  tar 
carbolic  liquid,  in  holes  dug  in  the  ground  with  tanks 
built  in  the  same,  and  left  in  there  for  several 
days,  then  taken  out  and  undergoing  the  other  pro- 
cess of  silicate  of  soda,  limewash  and  chloride  of  cal- 
cium, as  described,  will  render  them  proof  against 
fire  and  dry  rot. 


2n 


CEMENTS. 


The  following  Cements,  Whitewash  and  Concretes 
have  all  been  tested,  and  deserve  a  general  introduc- 
tion : 

The  Silica  Cement  a  Preservative  to  the 
Bottom  of  Iron  Ships. 

It  is  well  known  that  iron  ships  have  produced 
many  disasters  from  rusting  after  long  voyages ;  the 
experiments  tried  for  preventing  the  adherence  of 
barnacles  and  the  rusting  have  been  very  numerous. 
The  author  feels  quite  confident  of  success  by  the 
proper  application  of  a  silica  cement  prepared  by  a 
hot  solution  of  asphaltum  and  fine  sand,  manganese, 
and  liquid  silicate  of  soda,  and  putting  it  on  the  bot- 
tom of  the  iron  ships  by  means  of  a  brush,  and  before 
becoming  quite  dry  to  dust  over  the  paint  more 
powdered  manganese. 

The  Most  Adhesive  Insoluble  Cement. 

Blacklead,  6  lbs.,  are  mixed  with  3  lbs.  slacked 
lime,  8  lbs.  sulphate  of  raryta  are  mixed  with  7  lbs. 
of  linseed  oil ;  the  whole  mass  is  well  mixed  together 
to  a  uniform  consistency,  and  the  entire  mass  made 
more  plastic  with  concentrated  solution  of  silicate  of 
soda.  This  cement  may  be  used  for  numerous  pur- 
poses, where  hardness  and  adhesiveness  are  the  de- 
sired objects,  uniting  at  the  same  time  steam  and  hot 
water.    The  cheapest  Lubricator  for  locomotives,  en- 


CEMENTS. 


213 


gines  and  machinery  is  prepared  from  a  mixture  of 
silicate  of  soda  liquid  at  25®  B.'  added  to  fine  plum- 
bago, talc  and  aspestos  in  equal  quantities,  so  as  to  re- 
tain the  thin  plastic  condition,  and  capable  of  drop- 
ping it  on  the  journals  in  very  small  portions. 

The  Cheapest  Whitewash^  which  is  very  durable 
for  indoor  and  outdoor  work,  is  prepared  by  the 
following  composition  :  To  1  lb.  slacked  lime  and  1 
lb.  sulphate  baryta,  add  1  pint  of  silicate  of  soda  and 
1  pailful  of  hot  water ;  stir  the  materials  well  toge- 
ther, and  use  it  at  once.  If  the  color  is  intended  for 
a  yellow  wash,  add  a  quarter  of  a  lb.  chrome  yellow  ; 
if  for  a  blue  wash,  use  instead  of  the  latter  a  quarter 
of  a  lb.  of  ultramarine  (worth  six  cents)  ;  and  if  the 
paint  is  intended  to  coat  iron  railing,  stoves,  steam- 
boat chimneys,  and  to  obtain  a  brown  or  black  fire 
proof  paint,  add  half  a  pound  of  manganite,  an  oxide 
of  manganese,  or  the  pyrolusite,  which  is  the  black 
or  gray  peroxide  of  manganese. 

The  white  wash  or  yellow  wash  just  quoted  is  ex- 
tremely durable  and  cheayj  for  wooden  fences  along 
railroad  tracks,  canal  boats,  farm  houses,  and  other 
wooden  structures. 

The  Most  Durable  Aquarium  Cement. 

The  materials  of  a  water-resisting  composition  are 
prepared  by  mixing  finely  powdered  dry  silicate  of 
soda,  powdered  chalk,  and  fine  sand  in  equal  quan- 


214: 


CEMENTS. 


titles,  made  plastic  with  the  liquid  silicate,  and  ap- 
plied at  the  joints,  and  worked  over  with  fluid  chlo- 
ride of  calcium,  and  when  quite  dry  let  some  weak 
hydrofluoric  acid  pass  over  the  cemented  joints. 
This  cement  will  be  permanently  impervious  to  water, 
and  will  not  crack.  The  same  composition  is  quite 
suitable  for  brewries,  malt  houses,  linings  for  water- 
tanks,  and  cellars  into  which  water  flows. 

The  author  considers  it  advisable  to  show,  also,  the 
advantages  of  concrete  by  quoting  Tail's  system,  ap- 
plied in  Paris,  and  the  description  of  the  concrete 
bridge  at  London,  and  will  state  that  the  addition  of 
silicate  of  soda  to  the  concrete  will  undoubtedly  en- 
sure a  great  saving. 

Tail's  system  has  been  used  in  the  construction  of 
a  large  number  of  houses  in  Paris,  erected  under  the 
directions  of  the  emperor,  who  takes  great  interest  in 
the  improvement  of  the  working  classes.  This  con- 
has  also  been  applied  in  other  parts  of  Europe,  and 
to  some  extent  in  the  United  States. 

The  work  can  be  performed  by  ordinary  laborers, 
who,  after  four  or  five  days'  experience,  acquire  all 
the  requisite  expertness.  Even  boys  have  been  suc- 
cessfully employed  in  this  kind  of  building.  The 
only  skilled  workman  necessary  is  a  common  carpen- 
ter, whose  duty  is  to  adjust  the  framework  or  appa- 
ratus to  receive  the  successive  courses  of  material, 


CEMENTS. 


215 


and  place  joists,  doors,  and  window-frames  properly. 
»  The  apparatus  is  designed  to  construct  eighteen 
inches  in  height  daily  over  the  entire  extent  in  hand, 
what  is  done  in  the  evening  of  one  day  is  hard  next 
morning,  and  quite  strong,  the  best  proof  of  which  is 
that  the  wall  itself,  as  it  rises  in  height,  supports  the 
necessary  scaffolds.  A  double  curb,  entirely  sur- 
rounding the  upper  part  of  the  walls,  serves  to  hold 
the  plastic  material  in  place,  until  it  acquires  suflS- 
cient  hardness  to  support  itself. 

The  material  consists  of  one  part  of  Portland 
cement  to  eight  parts  of  coarse  gravel.  The  cement 
and  gravel  are  first  well  mixed  together  in  a  dry 
state,  and  when  this  is  done  it  is  damped  by 
means  of  a  large  watering-pot,  containing  some  hot 
silicate  of  soda  and  again  mixed  by  a  pronged  drag, 
such  as  is  used  for  dragging  dung  out  of  a  cart, 
until  the  entire  heap  has  been  wetted  and  mixed  to- 
gether. It  is  then  put  in  iron  or  zinc  pails  and 
poured  into  the  frame,  where  it  is  leveled  by  men 
stationed  for  the  purpose.  In  order  to  save  concrete, 
large  lumps  of  stones  or  brickbats  are  put  into  the 
centre  of  the  wall,  and  covered  over  and  about  with 
concrete.  Frost  does  not  affect  the  concrete  after  it 
has  once  set,  which,  with  good  cement,  will  be  in 
about  five  or  six  hours.  Nor  do  heavy  rains  appear 
to  injure  it  in  the  slightest  degree,  though  they  may 
chance  to  fall  ere  the  concrete  has  hardened.  The 


216  CEMENTS. 

walls  can  be  made  straight  and  even  as  it  is  possible 
for  walls  to  be,  and  the  corners  as  sharp  and  neat  as  > 
if  they  had  been  formed  of  the  most  carefully  dressed 
stone. 

Concrete  makes  excellent  floors,  and  the  walls  and 
floors  are  quite  impervious  to  vermin  of  all  kinds, 
and  also  to  wet.  Many  kinds  of  building  bricks  will 
absorb  water ;  hence,  brick  houses,  when  the  walls 
are  saturated  with  water,  are  cold.  This  is  not  the 
case  with  houses  constructed  of  concrete,  as  it  is  non- 
absorbent  of  moisture,  and  such  houses  must  be, 
therefore,  more  healthy. 

This  novel  mode  of  building  houses  has  excited 
great  interest  in  the  neighborhood  of  Runnamoat, 
Ireland,  and  the  proceedings  have  daily  attracted 
numbers  of  people  from  all  parts. 

While  concrete  may  be  used  in  constructing  build- 
ings of  every  description,  it  is  peculiarly  adapted, 
from  it  cheapness,  for  the  construction  of  cottages  for 
laborers,  and  also  for  farm  buildings.  Its  cost  is  not 
more  than  half  that  of  brick-work  ;  almost  any  mate- 
rial can  be  used  along  with  the  cement,  and  as  we 
have  already  shown,  the  most  ordinary  class  of  coun- 
try laborers  are  quite  competent  to  carry  out  the  de- 
tails of  the  system.  With  reference  to  its  adaptabil- 
ity for  large  buildings,  we  may  mention  that  a  ware- 
house seventy  feet  long,  fifty  feet  wide,  and  sixty  feet 
high,  five  stories  in  all,  has  been  erected  on  Mr. 


CEMENTS. 


217 


Tail's  system  for  Mr.  H.  Goodwin,  Great  Guilford 
street,  Southwark,  England,  and  that  gentleman  tes- 
tifies in  the  warmest  terms  to  its  satisfactory  charac- 
ter, and  is  making  arrangements  at  the  present  time 
for  the  construction  of  another  similar  building.  The 
warehouse  already  erected  has  attracted  universal  ad- 
miration from  the  practical  and  scientific  gentlemen 
who  witnessed  its  erection. 

The  chief  element  of  success,  when  the  cement  is 
of  good  quality,  seems  to  be  the  thorough  mixture  of 
the  dry  materials,  to  secure  uniform  strength. 

Concrete  Bridge. 

The  tests  applied  to  the  experimental  bridge  of 
concrete,  set  in  cement,  erected  over  that  branch  of 
the  Metropolitan  District  Railway  which  forms  one 
of  the  junctions  between  the  circular  line  and  the 
West  London  Extension,  prove  conclusively  the  re- 
liable character  of  concrete  exposed  to  compressive 
strains.  The  structure  experimented  upon  spans  the 
open  cutting  between  Gloucester-road  Station  and 
Earle's  Court  Road.  It  is  a  flat  arch  of  75  feet  span, 
and  7  feet  6  inches  rise  in  the  centre,  where  the  con- 
crete is  3  feet  6  inches  in  thickness,  increasing  to- 
wards the  haunches,  which  abut  upon  the  concrete 
skewbacks.  The  material  of  which  the  bridge  is 
made  is  formed  of  gravel  and  Portland  cement, 
blended  in  the  proportions  of  six  to  one,  carefully 


218 


CEMENTS. 


laid  in  mass  upon  close  boarding  set  upon  the  cen- 
'  tring,  and  enclosed  at  the  sides.  In  testing  the  bridge 
rails  were  laid  upon  sleepers  over  the  arch,  which 
brought  a  load  of  two  seventy-fifths  of  a  ton  per  foot 
upon  the  structure.  Seven  trucks,  weighing,  toge- 
ther with  their  loads,  forty-nine  tons,  were  formed 
into  a  train,  having  a  wheel  base  of  fifty-seven  feet ; 
hence  the  rolling  load  amounted  to  forty -nine-fifty- 
sevenths  of  a  ton  per  foot  run.  The  deflection  pro- 
duced by  the  passage  to  and  fro  of  this  train  four  timea 
was  noted  upon  a  standard,  cemented  to  the  side  of 
the  arch,  at  a  distance  of  one-third  the  span  from  the 
abutments.  When  one  side  of  the  bridge  was  loaded, 
the  extreme  rise  of  the  branch  on  the  opposite  side 
was  about  one-sixteenth  of  an  inch,  which  was  pro- 
duced by  a  maximum  strain  of  10  tons  14  cwt.  per 
square  foot.  At  a  subsequent  trial,  a  mass  of  gravel 
10  feet  wide  and  3  feet  thick  at  the  crown,  and  6  feet 
deep  at  the  haunches,  was  laid  over  the  bridge,  and 
upon  this  ballast  was  placed  the  permanent  way* 
After  an  interval  of  a  few  days,  the  trucks,  loaded  a& 
before,  were  passed  over  the  bridge,  at  first  in  pairs, 
and  finally  all  together.  In  this  test  the  strain  upon 
the  concrete  was  as  follows  : 

The  weight  of  the  arch,  as  before  7  tons  17  cwt. 

170  tons  of  ballast   4  tons  8  cwt. 

Strain  per  square  foot  from  dead  load  12  tons  5  cwt. 

Strain  per  square  foot  from  passing  load . .  2  tons  17  cwt. 

Total  strain  per  foot  15  tons  2  cwt. 


CEMENTS. 


219 


After  repeated  transit,  the  load  was  left  upon  the 
bridge  all  night,  and  the  arch,  upon  examination^ 
showed  no  signs  of  failure  or  distress  under  the  severe 
strains  to  which  it  had  been  exposed. 

The  Soluble  Glass  as  Manure  for  Grapevines* 

By  putting  the  dry  silicate  of  soda  at  the  roots  of 
grapevines,  witl^  or  without  the  addition  of  phosphate 
of  lime,  has  by  experiments  proved  of  immense  bene- 
fit to  the  thriving  of  the  vines  to  a  proper  thickness, 
and  the  grapes  of  uncommon  size. 

Soluble  Glass  a  Substitute  for  Soap. 

A  chemical  compound  is  effected  by  the  combina- 
tion of  an  alkali  with  silica,  which  possesses  a  greater 
affinity  to  the  first  than  the  acid  of  either  grease  or 
stearic  and  oleia  acids  have  in  coarser  soap.  On 
account  of  the  soap  which  generally  contains  the 
caustic  lime,  that  compound  prepared  by  the  admix-  * 
ture  of  soluble  glass  possesses  less  caustic  properties, 
and  acts  therefore  less  injurious  on  the  texture  of  cot- 
ton, linen  and  woolen  fabrics.  As  examples  of  this 
property  may  serve  the  treatment  of  lyes  with  wool 
or  silk,  which  are  actually  dissolved  by  the  same, 
while  the  soluble  glass  removes  but  externally  the 
adhering  dirt  without  any  injurious  action.  The 
slippery  and  adhesive  consistency  of  soluble  glass 
acts  likewise  beneficial  in  the  easy  washings  and  rins- 
ing with  water  of  the  impurities. 


220 


CEMENTS. 


There  are  roany  advantages  in  its  applications  on 
wool,  silk,  cotton  and  leather;  it  is  stronger  than 
common  soap,  requires  a  less  quantity,  and  either 
hard,  soft,  cold,  or  lukewarm  water  may  be  employed. 

The  labor  and  saving  of  fuel  is  an  advantageous 
economy ;  it  preserves  also  many  colors,  which  are 
not  fast,  much  better  than  common  soap  ;  it  resists, 
in  fact,  almost  all  colors.  From  one*  to  four  pounds 
liquid  glass  is  sufficient  for  100  pounds  of  water ; 
as  that  used  for  wool  is  quite  sufficient  for  a 
menstruum,  it  is  employed  quite  extensively  in 
Europe  for  washing  and  fullmg  of  wool,  and  it  has 
been  used  long  before  the  soluble  glass  was  known 
by  dissolving  flints  in  caustic  lye  prepared  from 
wood  ashes. 

The  Prussian  Government  has  found  it  advisable, 
for  the  introduction  of  the  soluble  glass  in  the  mili- 
»  tary  and  other  royal  institutions  and  prisons,  and 
also  for  the  paper  manufacturers,  and  their  extensive 
linen  establishments  ;  and  instituted  experiments  as 
to  practicability  of  a  general  economical  application. 

In  the  cotton  mills  it  has  proved  a  saving  of  50  per 
cent  by  substituting  it  for  starch  and  flour,  which  was 
so  indispensable  for  fastening  the  colors ;  and  in 
England,  thousands  of  pounds  sterling  have  been 
economized  by  its  application.  In  our  late  war  the 
consumption  of  the  soluble  glass  in  that  branch  of 
industry  of  the  United  States  was  very  extensive. 


CEMENTS. 


221 


The  soap  manufacturer,  who  formerly  did  use  rosin 
for  an  adulteration  or  admixture,  the  cost  of  which 
was  formerly  but  two  dollars,  but  rose  to  25  and 
30  dollars  per  bbl.  of  180  lbs.,  was  obliged  to  resort 
to  the  use  of  soluble  glass  in  its  various  forms  either 
as  liquid  or  jelly. 

Rosin  is  now  again  more  employed  than  the  sol- 
uble glass ;  not  however  for  the  reason  that  it  is 
better  as  a  sophisticator,  but  because  the  soap  maker 
has  an  idea  that  the  soap  formed  from  rosin  with  fat 
suited  better,  and  is  more  time  saving  ;  he  does  not 
consider  all  the  circumstances :  such  as  the  smell  and 
touch  produced  in  the  handling  or  washing  w^ith 
rosin  soap,  and  that  tlie  admixture  of  soluble  glass  is 
no  adulteration,  but  an  improvement,  and  that  it  is 
as  economical  as  rosin  soap. 

The  Soluble  Glass  a  Substitute  for  Glue. 

It  has  proved  quite  useful  in  applying  the  liquid 
glass  for  glueing  wood  and  paper  together,  instead  of 
the  common  glue,  and  it  is  sold  in  the  trade  as 
mucilage,  and  is  applied  on  paste  board  instead  of 
emery  or  corundum  paper,  used  by  cabinet  makers  and 
other  mechanics  for  polisliing.  As  a  paste  for  book- 
binders instead  of  glue,  starch  or  dexterine  it  has 
proved  quite  useful.  Earthenware  may  be  kept  more 
durable  by  lining  them  with  a  weak  solution.  It  is 
likewise  used  on  leather,  provided  the  same  is  not  ex- 
posed to  much  bending. 


222 


CEMENTS. 


The  glazing  or  enamelling  of  culinary  vessels, 
made  either  for  iron  or  stone  ware,  the  soluble  glass 
is  usefully  applied  in  the  following  manner  : — 

The  silicate  solution  of  soda  and  potasli  is  mixed 
with  thick  lime  water,  to  100  parts  of  the  silicate  add 
1  part  of  lime  water,  made  for  1  part  caustic  lime  to 
6  parts  of  water.  The  mixture  is  then  evaporated  to 
dryness  and  reduced  to  line  powder.  By  dipping  first 
tho  objects  to  be  glazed  in  the  liquid  silica,  the  pow- 
der is  then  sifted  over  them  ;  Avhen  dry,  the  operation 
is  repeated  again  ;  when  dry,  the  coating  becomes  so 
hard  that  it  cannot  be  rubbed  off  by  the  hands  ;  they 
are  then  treated  like  other  ware  by  putting  them  in 
a  furnace,  requiring  however,  not  a  very  great  heat. 

A  similar  process  is  to  prepare  a  mass  from  100 
parts  powdered  quartz,  80  parts  pure  potash,  10  parts 
saltpetre,  and  20  parts  slacked  lime,  which  mixture 
is  made  into  a  thin  paste  with  the  liquid  silicate,  and 
then  burnt.  This  glazing  is  very  durable  and  resists 
both  vegetable  and  mineral  acids  like  common  glass. 
It  requires  no  great  skill  to  execute  the  operation, 
and  the  expense  to  prepare  such  a  glazing  is  but  a 
trifle. 

Soluble  Glass  Application  foe  Yarious  Cements. 

Porcelain,  Glass  and  Metals  are  fastened  together 
when  broken,  either  by  the  liquid  or  gelatinous  sili- 
cate by  the  following  method :  Heat  the  object  to 


CEMENTS., 


be  fastened  together  to  that  of  boiling  water,  and 
apply  the  soluble  glass  on  both  sides  of  the  fracture, 
press  them  together  and  leave  them  in  a  warm  place 
for  a  fortnight,  when  they  will  be  fit  for  use.  Fluor- 
spar finely  ground,  black  oxide  of  manganese,  oxide  of 
iron  (crocus,)  finely  powdered  soluble  glass,  and 
many  more  refractory  substances  are  suitable  articles- 
to  mix  with  the  liquid  silica  for  the  various  cements- 
in  use  ;  a  cement  for  fastening  iron  in  stone,  glass  or 
wood  is  recommended,  consisting  in  1  part  prepared 
chalk,  1  part  marble  dust,  and  made  plastic  with  the 
liquid  silica,  or  1  part  powdered  soluble  glass,  2  parts 
powdered  fluorspar  made  into  a  paste  with  the  liquid^ 
silica,  and  this  is  for  pasting  labels  on  glass  bottles. 

Caseine  or  metamorphosed  milk  is  also  mixed  with 
the  liquid  silica,  and  makes  an  excellent  paste. 

Firejproof  Cement  is  composed  of  the  various 
oxides  of  iron,  and  formed  into  paste  with  the  liquid 
silica. 

The  Athens  Marble  Cement  is  composed  of  carbo- 
nate of  lime,  carbonate  of  magnesia  and  silica  with 
oxide  of  iron,  and  made  into  a  thin  liquid  and  ap- 
plied to  the  stone,  which,  on  drying,  is  permanently 
fastened  to  the  surface,  and  protects  it  from  smoke^ 
dust,  and  atmospheric  agents. 

Common  arid  fire  brick  acquire  great  strength  if 
the  silicate  of  soda  has  been  employed  in  the  manu- 
facture, and  become  indestructible,  they  are  then. 


CEMENTS. 


particularly  fit  for  baker  ovens,  wall  and  well  founda- 
tions and  furnace  beds. 

Glazed  paper  for  apothecarie's  use,  may  likewise 
be  prepared  with  the  soluble  glass. 

Metallio  Cement  is  formed  when  a  mixture  of 
•equal  parts  of  oxide  of  zinc,  per  oxyde  of  manganese 
and  litharge,  and  made  up  with  liquid  silica  and 
marble  dust,  and  applied  between  the  metals  to  be 
cemented. 

An  Impermeable  Cement  Resisting  Steam. 

It  is  prepared  by  mixing  six  parts  finely  powdered 
blacklead,  3  parts  slacked  lime,  and  8  parts  of  plaster 
of  paris,  made  into  consistency  by  the  liquid  silica. 

Zinc  Cement  for  stopping  cracks  in  "metallic  appa- 
ratus and  other  materials  is  made  by  mixing  equal 
weights  of  zinc  white  and  finly  powdered  soluble 
glass  with  a  solution  of  chloride  of  zinc  of  the  den- 
sity of  126 ;  it  sets  rapidly  and  resists  the  action  of 
most  agents.  The  simple  mixture  of  oxide  of  zinc 
with  a  solution  of  the  chloride  of  zinc,  has  also  been 
recommended. 

Cement  for  any  foundation  wall  is  made  by  mixing 
1  part  of  good  slacked  lime  with  3  parts  of  fine  sand, 
and  f  of  its  weight  of  finely  powdered  quick  lime  is 
added,  and  made  into  a  paste  with  the  liquid  silica ; 
this  mass  becomes  so  hard  in  4  days  that  a  piece  of 
sharp  iron  would  not  attack  it. 


CEMENTS. 


225 


The  Gypsum  and  Clay  Cement. 

This  cement  is  very  hard,  and  is  prepared  by  sui 
intimate  mixture  with  liquid  silica,  after  the  gypsum 
has  been  calcined,  and  it  is  preferred  to  lime  cement 
for  the  reason  that  by  the  action  of  lire,  it  becomes 
reconverted  into  lime,  which,  when  the  waters  from 
fire  engines  is  brought  to  bear  upon  it,  expands  much 
and  forces  out  the  walls  to  the  destruction  of  the 
walls. 

Hard  Adhesive  Cement. 

It  consists  in  mixing  5  parts  powdered  clay,  2  parts 
iron  fillings,  and  1  part  of  black  oxide  of  manganese, 
and  i  part  borax  made  into  paste  with  liquid  silica, 
when  dry  is  very  hard,  and  withstands  water.  Also 
a  mixture  of  manganese  and  zinc  wJdte  with  plaster 
of  paris  forms  a  very  hard  cement,  and  has  great 
adhesive  capacity. 

Drain  and  Gasjpipes  for  conducting  to  sewers 
and  houses,  may  be  made  as  permanent  as  iron  pipes 
by  using  a  hard  cement  consisting  of  hydraulic  lime, 
clay  and  sand,  mixed  with  fine  powdered  fluorspar 
and  soluble  glass,  all  made  plastic  by  the  liquid 
silica ;  this  mass  when  dry  and  burnt,  will  resist  a 
pressure  of  600  lbs.  to  the  square  inch,  while  iron 
pipes  burst  under  a  pressure  of  400  lbs.  to  the  square 
inch. 


S26 


CEMENTS. 


Cement  for  Closing  Cracks  in  Stoves,  &c. 

A  useful  cement  for  closing  up  cracks  in  stove  plates, 
stove  doors,  etc.,  is  according  to  a  notice  of  the  Scien- 
tific  American,  March  12th,  1870,  prepared  by  mix- 
ing finely  pulverized  iron,  such  as  can  be  procured  at 
the  druggists,  with  liquid  water  glass,  to  a  thick  paste, 
and  then  coating  the  cracks  with  it.  The  hotter 
the  fire  then  becomes  the  more  does  the  cement  melt 
with  its  metallic  ingredients,  and  the  more  completely 
will  the  crack  become  closed. 

Cement  foe  a  Cistern, 

Take  10  parts  of  Plaster  of  Paris. 
"      2  Glauber  Salts. 

"      4      "  Clay. 
"      4  Slacked  Lime. 

Made  in  a  plastic  cement  with  the  liquid  silicate  of 
soda,  and  before  it  hardens,  add  liquid  chloride  of 
calcium. 

I^or  sweetem7ig  the  water  in  cisterns,  which  is 
found  to  be  hard,  may  be  made  soft  by  one  gallon  of 
silicate  of  soda  in  the  cistern,  and  repeat  the  opera- 
tion onc3  a  month. 

The  hest  iron  cement  is  composed  of  calcined  plas- 
ter and  iron  filings,  from  each  10  parts,  4  parts  oxide 
manganese,  2  parts  slacked  lime,  made  plastic  with 
the  liquid  silicate  of  soda. 


CEMENTS. 


227 


The  most  refractory  cement  is  formed  from  silica, 
asbestos,  plumbago,  and  soapstone.  These  materials 
mixed  in  certain  proportions  and  made  plastic  by 
the  liquid  silica,  form  a  most  valuable  cement  for 
locomotive  journals  and  other  lubricating  purposes, 
for  lining  of  steam  boilers  as  well  as  coating,  for  fi- 
ling up  airholes  in  iron  castings.  By  the  addition  of 
peroxide  of  manganese,  it  may  be  much  improved, 
and  serve  as  a  permanent  paint,  which  is  fire  and 
waterproof. 

Besides  the  cements,  such  as  the  Portland,  Eoman, 
Keene's,  Parion  and  Martin's,  and  those  obtained  from 
the  Puzzuolanas  and  Trass,  as  obtained  near  Naples, 
and  from  the  extinct  volcanic  districts,  such  as  Viva- 
rais  in  Central  France,  at  Brihl,  near  Andernach  on 
the  Rhine,  and  also  near  Edinburgh  in  Scotland, 
and  the  Rosendale,  all  of  which  when  mixed  with 
coal  cinders,  slags  and  scoria  and  wood  ashes,  con- 
tain more  or  less  soluble  alkali,  and  have  a  con- 
siderable effect  in  hastening  the  absorption  of  the 
moisture,  and  facilitating  the  setting  of  the  lime 
and  sand.  There  are  also  the  burnt  clays  or  terra 
cotta,  and  are  frequently  used  as  artificial  stone,  but 
from  their  great  and  unequal  contraction,  and  the 
facility  with  which  they  are  acted  on  by  frost, 
are  rarely  satisfactory,  except  treated  with  soluble 
glass  as  has  been  described. 

There  are  also  many  varieties  of  concrete  now 


228 


CEMENTS. 


manufactured  in  vast  blocks  and  a  perfectly  solid 
mass,  which  replace  now  the  accumulations  of  rub- 
bish and  loosely  aggregated  stones,  once  thought 
sufficient  for  filling  up  intervals  between  walls  of 
solid  masonry,  especially  in  piers,  harbors,  and  other 
important  works,  and  to  which  the  name  concrete  has 
been  given,  and  means  a  species  of  rough  masonry, 
consisting  of  gravel  or  broken  stone  mixed  with  lime, 
the  latter  being  slaked  and  immediately  put  in  contact 
with  the  gravel.  When  lime  is  used  that  has  pre- 
viously been  worked  into  a  paste,  it  passes  by  the 
name  of  Beton,  and  the  Beton  Coignet  Building  has 
of  late  been  introduced  into  this  country,  and  to  a 
great  extent  substituted  for  brick  and  stone. 

Beton  Building. 

Of  all  the  compositions  which  in  late  days  have 
been  introduced  as  a  substitute  for  brick  or  stone- 
work, there  is  not  one  that  presents  more  attractions 
as  a  material  than  beton.  But  the  use  of  it  is  limited 
to  those  localities  where  water-lime  can  be  had  at  a 
reasonable  price.  For,  although  that  admirable 
cement  is  about  the  only  one  of  its  component  parts 
that  is  expensive,  yet  the  proportion  used  makes  the 
beton  more  costly  than  could  be  wished,  notwith- 
standing its  many  merits  as  a  building  material* 
There  need  not  be  any  stone  or  stone  chips  used  in 
the  making  of  beton.    All  that  is  required  to  make 


CEMENTS.  229 

a  quick-setting  and  very  durable  material  is,  sand 
three  parts  ;  water-lime,  one  part ;  broken  brick,  six 
parts.  The  water-lime  and  sand  should  be  well 
mixed  together,  dry.  Then  have  as  much  water 
thrown  on  as  will  make*a  moderately  stiff  mass,  when 
it  is  to  be  instantly  transferred  to  the  moulds,  which 
are  already  in  their  positions  on  the  walls,  and  the 
centre  to  be  packed  with  the  broken  brick,  which, 
being  very  porous,  will  receive  the  moist  cement 
readily  on  its  broken  faces,  and  help  to  set  tlie  whole. 
The  mode  of  proceeding  to  construct  the  courses  is 
by  means  of  moulds  easily  adjusted  and  taken  apart. 
They  are  to  be  calculated  so  as  to  inclose  a  block  of 
beton  of  the  required  thickness  of  the  wall,  and  of, 
say,  half  again  that  thickness  in  length.  Their 
height  may  be  ten  inches.  Thus,  if  the  wall  be 
twelve  inches,  the  block  will  be  the  same,  and  also 
eighteen  inches  long  by  ten  inches  high. 

We  will  proceed  to  describe  the  operation  of  build- 
ing as  carried  out  in  the  construction  of  a  beton  house 
at  Black  Eock,  near  Buffalo,  New  York,  some  years 
ago.  The  lines  being  laid  out,  the  basement  was  ex- 
cavated to  a  depth  of  six  feet,  and  the  trenches  for 
the  foundation  walls  dug  out  one  foot  and  a  half  be- 
low the  bottom  of  the  basement.  These  trenches 
were  two  feet  and  a  half  wide,  that  is,  three  inches 
on  each  side  wider  than  the  basement  wall  above 
them.    The  basement  was,  therefore,  dug  just  three 

10 


230 


CEMENTS. 


inches  wider  than  the  plan,  all  around,  and  this  was 
done  to  leave  room  for  the  placing  of  the  moulding- 
boxes  with  their  rods.  The  bottom  of  the  trenches 
was  made  level,  and  these  were  Ulled  with  concrete 
composed  of  gravel,  six  parts ;  sand,  four  parts  ;  and 
quick-lime,  one  !ind  a  lic^lf  part,  with  sufficient  quan- 
tity of  silicate  of  soda,  so  as  to  make  the  composition 
plastic.  When  this  mass  was  well  mixed  and  turned 
over  three  or  four  times,  it  was  thrown  into  the  tren- 
ches in  layers  or  courses  of,  say,  four  inches  in  depth. 
Each  course  was  spread  over  the  whole  of  the  founda- 
tion trenches,  until  they  were  all,  including  those  of 
the  foundations  of  cross-walls,  filled.  When  the  sur- 
face of  the  basement  or  cellar  bottom  was  reached, 
then  the  whole  area  was  gone  over  with  a  coat  of 
gravel ;  and  over  this  was  poured  a  creamy  mixture 
of  water-lime  and  sharp  river  sand,  in  equal  propor- 
tions, imtil  the  whole  was  flush.  This  was  done  on 
Saturday,  and  on  the  following  Monday  the  floor  was 
hard  enough  to  walk  upon.  The  basement  walls 
were  now  commenced  in  the  manner  here  described. 
The  lines  of  the  walls  were  carefully  laid  out,  and 
.angle-moulds  placed  at  each  corner,  with  straight 
moulds  set  at  equal  distances  all  along. 


 ^  >^  < 


CEMENTS. 


231 


A  corner  mould  and  three  or  four  straight  moulds 
are  sufficient  to  work  with  :  but  the  greater  the  num- 
ber of  moulds  the  more  expeditiously  the  operation 
of  building  goes  on.    When  all  was  ready,  the  corner 
moulds  were  filled  first,  and  then  the  other  moulds 
regularly  in  turn.    When  all  were  filled,  the  moulds 
were  taken  apart  and  set  up  at  other  points  along  the 
walls ;  but  sufficient  time  was  given  for  the  beton  to 
become  hard  enough  to  admit  of  being  uncovered. 
The  walls  being  thus  gone  around,  the  next  operation 
was  to  inclose  the  spaces  between  the  beton  blocks, 
and  this  was  done  by  using  the  sides  of  the  moulds, 
without  the  ends,  and  holding  them  in  place  by  the 
following  means  :    Two  pair  of  pieces  of  scantling, 
say  two  by  three  inches  each,  and  two  feet  long,  were 
set  upright  at  each  end  of  the  side-boards,  and  bear- 
ing them  against  the  beton  blocks.    At  the  middle 
of  their  length  they  were  held  by  the  rods  and  screws 
used  in  the  moulds ;  and  their  upper  ends  being  kept 
apart  by  sticks  of  the  necessary  length,  the  boards 
were  thus  clutched  and  kept  in  place.    These  in- 
closed spaces  were  now  up  flush,  in  the  same  manner 
as  the  moulds,  and,  by  packing  and  tamping,  the  con- 
nections were  made  so  complete  as  to  render  the 
whole  a  uniform  mass.    As  each  course  was  in  this 
manner  completed,  the  moulds  were  laid  for  a  new 
one,  taking  care  to  break  joint,  although  no  joint  waa 
visible,  yet  this  precaution  was  taken  to  avoid  any: 


232 


CEMENTS. 


continuous  joint  or  point  of  imperfect  connection. 
Where  doors  or  windows  occurred,  the  moulds  were 
placed  correspondingly,  on  either  side  of  such  open- 
ing ;  for  it  may  be  observed  that  there  is  no  neces- 
sity for  the  fixing  in  of  the  frames  until  the  work  is 
all  sufficiently  set.  However,  it  is  necessary  to  insert 
in  these  moulds,  at  doors  and  windows,  at  the  ends 
which  will  form  the  jambs  of  such,  pieces  of  scant- 
ling, called  stops,  say,  four  inches  thick,  and  in 
width,  sufficient  to  permit  the  future  frame  to  rest 
five  or  six  inches  back  from  the  outer  face  of  the  wall. 
Of  course,  the  frame  can  be  set  up  and  these  jambs 
worked  up  to  it,  but  it  is  more  troublesome  and  will 
scarcely  make  as  good  a  job.  The  window-sills  and 
caps  were  provided  for  in  like  manner  ;  and  there  was. 
a  splay  left  in  the  window  jambs,  by  meaus  of  angu- 
lar pieces  being  added  to  the  above-mentioned  stops, 
which  gave  the  required  mold  to  the  beton.  When 
the  level  of  the  ceiling  was  attained,  the  fiooring 
joists  were  all  set  up  in  their  places,  and  temporary 
bridgings  of  plank  fixed  between  every  pair,  so  as  to 
hold  the  beton,  which  was  thus  continued  up,  making 
a  compact  bed  for  the  joists,  and  effectually  prevent- 
ing the  lodgment  of  vermin.  The  short  boards  or 
pieces  here  used  may  be  removed  when  the  work  i& 
set,  as  they  will  be  wanted  again  on  the  next  floor. 
In  the  building  we  describe  they  w^ere  left  in,  but  it 
is  not  at  all  necessary. 


CEMENTS. 


233 


The  joists  being  all  flushed  up  with  beton,  the  floor 
boards  were  nailed  down  and  the  beton  again  flushed 
up  to  the  surface  of  the  floor.  The  moulds  were  now 
placed  for  the  walls  of  the  principal  story,  which 
being  six  inches  less  than  those  of  the  basement,  the 
ends  of  the  moulds  were  made  in  accordance  with  the 
new  thickness,  namely  twelve  inches,  and  the  work 
went  on  as  before,  with  the  exception  of  the  corners 
of  the  main  walls,  which  were  rounded  by  means  of 
blocks  of  the  necessary  shape  being  set  in  the  angle. 
This  rounding  off  of  the  walls  on  the  outer  corners 
gives  a  very  neat  appearance,  without  adding  to  the 
cost.  On  the  contrary,  it  economizes  the  material ; 
for  the  thickness  at  these  corners,  instead  of  being 
greater  on  the  diagonal,  is  exactly  the  same  as  that  of 
the  straight  walls  throughout.  In  the  manipulation 
of  the  beton  for  the  walls  of  the  superstructure,  it  was 
deemed  advisable  to  pack  the  front  of  each  mould  with 
a  purer  or  finer  coat  of  cement  than  that  used  at  the 
heart,  or  even  at  the  back,  so  as  to  give  one  uniform 
face  to  the  outside.  This  face  was  carefully  troweled 
into  the  bed  made  for  it  in  the  mould  by  working 
back  the  coarser  beton  in  which  the  broken  brick  was 
packed.  In  the  top  of  the  first  tier  of  blocks  forming 
the  course,  an  angle  mould  was  laid  along  and 
pressed  into  the  fine  beton  forming  the  outside  face. 
And  on  the  bottom  of  the  next  tier  of  moulds  a  cor- 
responding angle-mould  was  laid  and  the  beton  cast 


234 


CEMENTS. 


£rmly  around  it.  And  thus  every  course  was  treated' 
The  consequence  was  that  the  >  cincture  left  on  the 
removal  of  these  moulds  produced  an  effect  on  the 
exterior,  remarkably  like  coursed  masonry,  the  course 
lines  being  of  the  >  shape,  and  about  two  inches 
wide  and  one  inch  and  a  half  deep.  Any  other  sec- 
tion of  cincture  can  be  moulded  in  to  suit  another  de- 
sign of  building.  After  each  course  was  uncovered, 
these  sunken  mouldings  were  finished  smooth  by 
working  a  whole  mould  of  the  >  shape  along  them, 
backward  and  forward.  Perpendicular  moulds  of 
like  shape  might  have  been  made  to  mark  out  each 
block,  and  no  doubt  would  have  much  improved  the 
appearance  of  the  building.  The  sunken  horizontal 
courses  were  carried  all  around  the  house  and  pro- 
duced a  good  effect.  The  next  floor  was  flushed  up 
at  the  joists  precisely  in  the  same  manner  as  the  first, 
or  principal  floor.  The  windows  and  doors  were  all 
set  in  and  worked  up  to.  But  this,  as  was  before  ob- 
served, is  not  the  better  way.  The  sills  and  lintels 
were  of  oak,  but  the  latter  did  not  show  on  the  out- 
side. It  would  be  much  better  to  have  stone  sills 
and  lintels.  The  partition  walls  were  six  inches 
thick,  and  were  cast  in  unbroken  courses,  with  the 
exception  of  openings  for  doors.  The  door-cases 
were  set  in  and  worked  up  to.  Blocks  were  nailed 
to  the  floor  at  the  walls  and  partitions  to  receive  the 
base-boards  of  the  apartments,  and  these  blocks  were 


CEMENTS. 


235 


covered  up  in  the  beton.  In  like  manner,  there  were 
blocks  inserted  for  nailing  finisliings  of  windows  and 
doors  to,  and  for  holding  the  horizontal  slats  from 
which  to  hang  pictures.  The  roof  was  a  gabled  one, 
of  a  fourth  pitch  ;  but  a  Mansard  would  at  this  day- 
be  a  great  improvement.  The  walls  were  skim- 
coated  on  the  inside  of  the  house,  and  the  best  rooms 
were  hard  finished.  Nothing  can  be  easier  for  the 
plasterer  to  make  a  truly  workmanlike  job  with,  for 
his  material  is  sure  to  adhere  to  it.  There  is  little 
more  to  add,  save  tbat  the  chimnej-flues  were  all  cast 
round  by  means  of  stove-pipes  used  as  moulds,  and 
left  in.  This  is  not  a  good  plan,  as  the  stove-pipe 
will  corrode  after  a  time,  and  it  is  very  difficult,  if 
not  impossible,  to  remove  it.  It  would  be  better  to 
use  a  movable  cylinder  mould  with  a  handle,  and 
have  the  flue  finished  smooth  in  beton.  The  chimney 
shafts  can  be  very  ornamentally  finished  with  terra 
cotta  caps.  To  those  who  can  procure  water-lime  at 
anything  like  a  reasonable  i)rice,  we  would  strongly 
recommend  beton  as  a  particularly  applicable  mate- 
rial. It  is  warm  in  winter,  cool  in  summer,  and  at 
all  times  dry  and  healthful.  In  mixing  common 
lime  with  it — of  course  for  economy's  sake  alone — it 
will  be  well  to  bear  in  mind  that,  while  quicklime 
swells  in  slacking,  say  one-fourth,  water-lime,  on  the 
contrary,  shrinks  about  a  fifth.  By  experiment  on 
th:  limes  to  be  used,  exactness  can  be  obtained.  And 


236 


ESSAYS  RELATING  TO  THIS  TREATISE. 


by  thus  calculating,  the  two  may  be,  so  to  speak, 
dovetailed  into  each  other.  —  Manufacturer  and 
Builder. 

Essays  Relating  to  this  Treatise. 

The  following  essays  on  the  origin  as  well  as  functions  of  car- 
bonic acid,  limestones,  alkalies,  silica,  etc.,  follow  herewith  in 
order  to  explain,  in  the  first  place,  what  a  powerful  influence  car- 
bonic acid  exercises  in  the  application  of  soluble  or  water  glass 
for  all  purposes  of  domestic  economy,  how  carbonic  acid  acts  in 
the  sedimentary  rocks,  and  whether  derived  directly  from  the 
atmosphere  or  from  subterranean  decomposition,  produce  the 
disintegration  of  carbonate  of  lime  from  siliceous  substances. 

The  sources  of  limestones  from  the  ocean  bed  and  coral  reefs, 
and  the  subsequent  formation  of  various  limestone  rocks,  and 
application  of  the  same  for  our  purposes  ;  the  origin  of  the  alkalies 
as  are  employed  in  the  manufacture  of  soluble  glass. 

The  silica  in  all  its  applications  for  domestic  purposes,  explain- 
ing the  immense  variety  of  forms  as  found  in  nature,  and  uses  in 
the  manufacture  for  soluble  and  every  other  species  of  glass,  and 
forms  an  interesting  guide  for  the  production  of  plain  and  colored 
glass,  and  the  green  sand  formation  of  New  Jersey. 

I.  Essay  on  Carbonic  Acid. — By  Dr.  Lewis 
Feuchtwanger. 

"  Carbonic  acid,  the  pabulum  of  the  organic  and 
inorganic  world." 

According  to  the  ancient  philosophers,  the  sim- 
ple bodies  or  elementary  principles  from  which 
all  the  varieties  of  matter  are  composed,  were  but 


ESSAY  ON  CARBONIC  ACID. 


237 


four,  namely :  fire,  air,  water  and  earth.  This 
notion,  after  having  for  ages  formed  a  part  of 
the  creed  of  the  learned,  has  been  completely  ex- 
plained by  the  light  of  modern  science,  though  it  is 
not  yet  extinct  among  the  vulgar.  The  alchemical 
writers  of  the  middle  ages  added  to  these  principles 
some  others,  as  salt,  sulphur  and  mercury,  to  which 
terms,  however,  they  attached  ideas  very  different 
from  those  that  belong  to  them  at  present,  and  into 
the  nature  of  which  it  is  not  necessary  to  inquire. 
Some  of  the  alleged  elements  of  the  olden  chemists 
are  now  known  only  to  exist  in  imagination,  and 
others  are  ascertained  to  be  by  no  means  simple  sub- 
stances. Thus  air  is  found  to  consist  of  two  difierent 
elastic  fluids  or  gaseous  bodies,  which  may  be  separa- 
ted by  various  processes,  and  exhibited  apart  from 
each  other.  Water,  also,  has  been  ascertained  to  be 
a  compound,  which  may  be  analyzed  or  decomposed 
so  as  to  produce  two  distinct  kinds  of  gases,  which 
may  be  separately  collected,  and  when  again  mixed 
together  in  proportions,  they  may  be  made  to  form 
water  by  their  union. 

Other  bodies  formerly  esteemed  simple  have  yielded 
to  the  analytical  processes  of  modern  chemistry  ;  but 
there  is  a  certain  number  of  substances  which,  either 
in  the  state  in  which  they  are  presented  to  us  by 
nature,  or  as  they  are  procured  in  various  operations 
by  art,  have  resisted  all  attempts  at  further  decompo* 


538 


ESSAY  ON  CARBONIC  ACID, 


fiition,  and  which,  therefore,  as  before  stated,  inuBt 
be  regarded  as  simple  substances.  Their  number  is 
not  very  great,  amounting  to  about  sixty-three,  and 
it  is  not  unlikely  that  the  future  researches  of  chem- 
ists may  demonstrate  some  of  these  bodies  to  be  com- 
pounds, as  we  have  the  latest  example  in  the  discov- 
ery of  Graham,  who  converted  the  hydrogen  from  its 
gaseous  form  into  a  metal  hydrogenium.  At  the 
same  time  it  is  probable  that  additions  may  be  made 
to  the  class  of  elementary  substances  in  consequence 
of  future  discoveries,  several  of  those  now  admitted 
into  this  class  having  become  known  to  us  but  very 
recently. 

Some  of  those  elementary  bodies  are  widely  and 
abundantly  disposed  throughout  the  three  kingdoms 
of  nature,  either  alone  or  in  a  state  of  composition, 
while  those  appear  to  be  of  very  rare  occurrence,  or 
at  least,  they  have  hitherto  been  met  with  only  in 
small  quantities  and  in  a  few  situations.  The  whole 
of  the  elementary  substances  may  be  arranged  in  two 
divisions  :  the  first  comprehending  those  which  are 
not  of  a  metallic  nature,  and  those  which  are  regard- 
ed as  metals,  although  many  exhibit  properties  differ- 
ing considerably  from  those,  which  are  well  defined 
as  such,  like  gold,  silver,  mercury,  iron,  lead,  &c. 
The  accompanying  table  shows  all  the  elements.  The 
non-metals  are  in  large  capitals,  and  the  metals  in 
small  type : 


ESSAY  OX  CARBONIC  ACID. 


239 


Hydrogenium 


Mercury  

Magnesium  

Manganese  

Molybdenum.  ., 

Nickel  

Niobium  

NiTROdEN  

Osmium  

OXYGEK  

Palladium  

Phosphorus  

Pelopinm  

Platinum  

Potassium  

Ehodium  

Rubidium  

Ruthenium.  ... 

Bblenium  , 

Silver  

Silicon  

Sodium  

Strontium  

SXTLPHUR  , 


Discoverer. 


Woebler,  Germany  

Basil  Valentine  

Paracelsus  knew  it  in  XVI.  cen- 
tury; George  Brandt,  Sweden.  .. 

SirH.  Davy,  England  

Agricola   

Sir  H.  Davy,  England  

Ballard,  France  

Stromeyer  

Bunseu  

Sir  II.  Davy  

Lavoisier  established  the  diamond 
as  carbon  ^  

Hisingcr,  Sweden  

Scheele,  Sweden  

Vauquclin.  Franco  

Brandt,  Sweden  

Known  by  the  ancients  

Mosandcr  


Sheele  investigated  and  discovered, 
but  never  separated  it  

Oxide,  by  Vauquclin,  1797;  metal 
by  Wo'liier  

Known  by  the  ancients  

As  gas,  by  Cavendish,  England  

Graham  


Reich  found  in  zinc  ore  

Courtoise,  France  

Tenant   

Known  from  early  time  

Mosander  

Known  by  the  ancients  

Oxide,  by  Arfvedson,  Sweden,  1818; 

metal  by  Brai  d  

Known  to  the  ancients  

Bussy,  France  

Gahn ,  Sweden  

Sheele,  Sweden  

Bergman,  Sweden  

Hatchett  

Dr.  Rutherford,  Scotland  

Tenant  

Dr.  Priestly,  England  

Dr.  Wollaston,  England  

Brandt,  Hamburg  

H.  Rose  

Charles  Wood.  Jamaica  

Sir  H.  Davy,  England  

Dr.  Wollaston,  England  

Bnnsen  

Clauss  

Berzelius,  Sweden  

Known  to  the  ancients  

Berzelius,  Sweden  

Sir  H.  Davy  

Sir  H.  Davy  

Natural  product  


Date. 

o 
n 

oc 

At.  Wt. 

o 

cu 

OQ 

1828 

Al 

27.4 

2.6 

1450 

8b 

1^2 

6.7 

1783 

As 

75 

3.7 

1808 

Ba 

lo  < 

1530 

Bi 

210 

9.7 

1807 

B 

jj 

1.47 

1826 

Br 

80 

5.54 

1817 

Cd 

112 

8.6 

1861 

Cs 

13;3 

1808 

Ca 

40 

1.58 

1775 

C 

12 

3.5 

1804 

Ce 

92 

1774 

CI 

35.5 

.2454 

1797 

Cr 

52.2 

1733 

Co 

58.7 

7  7 

Cu 

63.5 

8.9 

1843 

D 

95 

E 

112.6 

F 

19 

1.060 

1828 

Gl 

9.8 

Au 

197 

12. 

176G 

H 

1 

.69 

1869 

H 

1.708 

1861 

In 

35.91 

ISOl 

I 

127 

4.95 

1803 

Ir 

198 

Fe 

50 

7.79 

1839 

La 

92 

Pb 

207 

11.4 

1820 

Li 

7 

.59 

Hp 

200 

13.5 

1829 

•v.g 

24 

1.74 

1774 

Mn 

55 

7. 

17S2 

Mo 

96 

8.6 

1775 

Ni 

5S.7 

8.2 

Nb 

94 

1772 

N 

14 

.972 

1803 

Os 

199.2 

21. 

1774 

0 

IG 

1803 

Pa 

li'6.6 

11.3 

1669 

p 

31 

2.0 

1S46 

1741 

Pt 

197.5 

21. 

1S07 

K 

39.1 

865 

1804 

Rh 

104.4 

11. 

1861 

Kb 

85.4 

Ku 

104.4 

1818 

Se 

79.5 

4.3 

Ag 

108 

10.4 

1824 

?i 

28 

2.49 

1807 

Na 

23 

.15 

isos 

Sr 

87.5 

2.53 

S 

32 

2.0 

240 


ESSAY  ON  CARBONIC  ACID. 


Name. 


Discoverer. 


Tantalium  I 
(Columbium)  j  i 

Tellurium  

Thallium  I 

Thorium'  

Tin  j 

Tintanium  

Tungsten  

Uranium  

Vanadium  

Yttrium   | 

Zinc  I 

Zirconium  


Ilatchet  and  Eckoberge,  1801; 

duced  by  Berzelins  

Klaproth,  Berlin   

Crookes  and  Lane  

Berzelius,  Sweden  

Known  by  the  ancients.  

Vauquelin  

M.  M.  D''E]huyard,  Spain  

Klaproth,  Berlin  

Sefstrom,  Berzelius,  and  Del  Eio 

Gadolin,  Sweden  

Henkel  

Berzelius,  Sweden  '.  


Date. 

s 

ti 
O 

cc 

< 

1824 

Ta 

1S2 

1797 

Te 

12S 

6.2 

1861 

Tl 

203 

Til 

Sn 

118 

7.29 

1796 

Ti 

50 

4.3 

1781 

W 

184 

17.5 

1789 

U 

120 

1830 

V 

51.8 

1794 

Y 

18.6 

1721 

Zn 

65.2 

6.9 

1824 

Zr 

89.6 

4.3 

OarhoUj  one  of  these  elementary  bodies,  is  the 
most  remarkable  substance  in  nature,  and  enters 
largely  into  the  composition  of  most  substances  be- 
longing to  the  animal  and  vegetable  kingdom,  and 
forms  also  the  basis  of  many  of  the  combustible  mine- 
rals, as  bitumen,  coal,  plumbago,  amber.  In  the 
form  of  charcoal,  procured  by  charring  or  distilling 
without  the  access  of  air,  wood,  animal,  and  some 
other  substances,  carbon  is  obtained  in  a  separate 
state  or  merely  intermixed  with  small  portions  of 
earths  or  salts.  The  charcoal  used  in  the  various 
arts  and  manufactures  is  commonly  prepared  on  an 
extensive  scale  by  the  imperfect  combustion  of  wood, 
built  up  in  large  piles  and  covered  with  turf,  or  by 
the  distillation  of  wood  in  cast-iron  cylinders.  Lamp- 
black is  also  chiefly  composed  of  charcoal,  consisting 
of  soot  collected  from  the  combustion  of  the  refuse 
resin  obtained  in  making  turpentine.    Ivory  black  is 


ESSAY  ON  CARBONIC  ACID. 


241 


another  carbonaceous  substance,  which  results  from 
the  burning  of  bones  in  close  vessels.  Coke  is  chiefly 
composed  of  charcoal,  arising  from  the  distillation  of 
coal,  as  in  the  coal  gas  manufactories.  Pure  carbon 
is,  however,  represented  in  the  diamond.  Chemical 
investigation  has  proved  that  the  diamond,  when  ex- 
posed to  a  very  high  temperature,  and  especially  if 
confined  in  oxygen  gas,  will  burn  like  charcoal  and 
exhibiting  the  same  product.  This  splendid  gem,  in 
its  natural  state,  is  composed  of  octahedral  crystals, 
and  Sir  Isaac  Newton  ascertained  from  observing, 
that  it  was  possessed  of  high  refractive  powers  and 
•an  inflamable  substance.  It  is  brittle,  but  appears  to 
be  harder  than  any  other  substance.  Hence  the 
powder  of  the  diamond  is  used  for  cutting  and  polish- 
ing the  hardest  gems,  and  the  diamond  itself,  as  the 
most  ornamental  article  of  jewelry.  How  diamond 
was  formed  is  a  matter  of  enquiry.  It  certainly 
■could  not  have  been  produced  at  a  high  temperature, 
because  when  strongly  heated,  apart  of  the  air  or 
oxygen,  the  diamond  swells  up,  and  is  converted  into 
a  black  mass  resembling  coke. 

Carbon,  as  commonly  procured  by  distilling  wood, 
is  a  good  conductor  of  electricity,  though  a  bad  con- 
ductor of  heat.  It  remains  unchanged  by  air  or 
water  at  common  temperature,  but  when  highly 
heated  readily  burns  in  oxygeu,gas  or  common  air. 

It  has  the  property  of  destroying  the  smell  and 


242 


ESSAY  ON  CAEBONIC  ACID. 


taste  of  many  animal  and  vegetable  substances,  and 
it  powerfully  resists  putrefaction  ;  so  that  tainted 
meat,  if  covered  with  new  burnt  charcoal  for  a  few 
hours,  becomes  perfectly  sweet.  The  colors  of  vege- 
table substances  are  also  effected  by  charcoal ;  hence 
it  is  sometimes  added  to  port  wine  for  the  purpose  of 
giving  it  a  tawny  hue.  Yinegar  boiled  with  it  be- 
comes colorless,  and  it  is  largely  used  in  refining 
sugar,  particularly  the  animal  charcoal.  Freshly 
prepared  charcoal  largely  absorbs  various  gases. 
This  property,  however,  depends  on  the  texture  of 
the  charcoal,  and  the  difierent  kinds  absorb,  in  vari- 
ous proportions,  aqueous  vapors  contained  in  the  air. 
Carbon  unites  with  oxygen  to  form  three  or  more 
compounds,  an  oxide  and  various  acids.  The  car- 
bonic oxide  is  a  gaseous  body,  and  was  discovered  by 
Dr.  Priestley,  and  this  is  produced  from  the  decom- 
position of  the  compounds  containing  carbonic  acid, 
as  by  the  heating  in  an  iron  retort  a  mixture  of  chalk 
and  charcoal,  or  of  equal  weights  of  chalk  and  iron 
or  iron  filings.  The  gas  resulting  from  either  of 
these  operations  may  be  collected  in  a  jar  inverted 
and  filled  with  water,  and  then  purified  by  agitating 
it  with  lime  water.  It  is  destitute  of  color  and  taste 
and  has  a  disagreeable  smell,  and  is  highly  injurious 
to  animals,  producing  giddiness  and  fainting  if  re- 
spired when  mixed  ^^ith  atmospheric  airs.  We  have 
many  instances  where  many  families  were  found  suf- 


ESSAY  ON  CAEBONIC  ACID. 


245 


focated  in  the  morning,  the  cause  being  that  they  had 
a  coal  fire  burning,  in  close  apartments,  before  retir- 
ing  to  bed. 

Carhonio  acid,  or  called  fixed  air. — It  is  obtained 
when  the  carbonic  oxide  is  mixed  with  half  its  vol- 
ume of  oxygen,  and  exposed  in  a  detonating  tube 
to  the  electric  spark,  when  an  explosion  takes  place, 
and  carbonic  acid  is  formed  equal  in  bulk  to  the  car- 
bonic oxide.  It  is  a  compound  gas,  and  is  formed 
both  by  art  and  nature  in  a  variety  of  processes.  An 
abundant  production  of  this  gas  takes  place  in  the 
combustion  of  animal  and  vegetable  substances  in 
general ;  but  the  most  interesting  example  of  the  for- 
mation of  carbonic  acid  occurs  when  the  diamond  is- 
intensely  heated  in  common  air  or  oxygen  gas.  This 
extremely  dense  and  apparently  permanent  substance 
under  these  circumstances  becomes  wholly  converted 
into  carbonic  acid,  a  result  which  plainly  demon- 
strates it  to  consist  of  carbon  alone.  Carbonic  acid^ 
when  wanted  for  the  purpose  of  experiment,  may^ 
however,  be  most  readily  obtained  by  decomposing 
the  combinations  of  this  acid  with  alkalies  or  earths. 
Thus  chalk  or  marble,  when  dropped  in  small  frag- 
ments into  dilute  sulphuric  or  hydrochloric  acids, 
will  give  out  abundance  of  this  gas,  w^hich  may  be 
collected  over  water  ;  they,  however,  absorb  a  large 
portion  of  it,  even  at  common  pressures  and  tempera- 
tures. 


ESSAY  ON  CARBONIC  ACID. 


Carbonic  acid  gas  is  destitute  of  color  or  smell,  but 
like  other  acids,  it  has  a  sour  taste.  It  is  much 
heavier  than  common  air,  and  is  uninflammable,  ex- 
tinguishing burning  bodies  which  are  plunged  into  it. 
■Owing  to  its  great  specific  gravity,  it  may  be  poured 
from  one  vessel  to  another,  like  a  liquid,  and  will  re- 
main for  some  time  at  the  bottom  of  an  open  jar  with- 
out mixing  with  the  atmospheric  air  above  it.  It  is 
poisonous  to  animals,  and  cannot  be  breathed  with- 
out the  utmost  danger.  The  famous  Poison  Valley 
in  the  Island  of  Java,  has  been  visited  by  travelers, 
who  relate  that  they  took  with  them  two  dogs  and 
some  fowls  to  try  experiments  in  the  poisonous  val- 
ley. When  arriving  at  the  foot  of  the  mountain,  and 
when  within  a  few  yards  of  the  valley,  they  experi- 
enced a  strong,  nauseous,  suffocating  smell.  The 
valley  is  about  half  a  mile  in  circumference,  and  a 
depth  of  30-35  feet,  flat  bottom,  and  no  vegetation, 
strewed  with  some  large  sized  stones,  and  the  whole 
covered  with  the  skeletons  of  human  beings,  tigers, 
pigs,  deer,  peacocks,  and  all  sorts  of  birds.  Did  not 
perceive  any  vapors  or  any  opening  in  the  ground, 
which  appeared  to  be  of  a  hard,  sandy  substance. 
They  descended,  after  lighting  a  cigar,  and  assisted 
by  a  bamboo,  within  eighteen  feet  of  the  bottom, 
where  they  did  not  experience  any  difiiculty  in 
breathing,  nor  did  any  oflFensive  smell  annoy  them. 
They  then  fastened  a  dog  to  the  end  of  a  bamboo, 


ESSAY  ON  CARBONIC  ACID. 


245 


and  after  the  lapse  of  fourteen  seconds  he  fell  on  his 
back ;  did  not  move  his  limbs,  but  continued  to 
breathe  eighteen  minutes.  Another  one  was  sent  in, 
and  he  fell  in  ten  minutes  on  his  face,  and  continued 
to  breathe  for  seven  minutes  longer.  A  fowl  was 
then  tried,  which  died  in  one  minute  and  a  half.  On 
the  opposite  side,  near  a  large  stone,  w^as  the  skeleton 
of  a  human  being,  who  must  have  perished  on  his 
back  with  the  right  hand  under  his  head. 

It  is  for  this  reason  that  the  proportion  of  this  gas 
contained  in  the  air  is  so  very  small.  Were  this 
proportion  much  greater  than  it  is,  animals,  as  they 
are  now  constituted,  could  not  breathe  the  air  with- 
out much  injury.  On  the  other  hand,  that  growing 
plants  may  be  able  to  obtain  a  sufficient  large  and 
rapid  supply  of  carbonic  acid  from  a  gaseous  mixture 
which  contains  so  little,  tliey  are  made  to  hang  out 
their  many  weaving  leaves  into  the  atmosphere.  Over 
the  surface  of  these  leaves  are  sprinkled  countless 
pores  or  mouths,  which  are  continually  employed  in 
separating  and  drinking  in  carbonic  acid  gas.  The 
millions  of  leaves  which  a  single  tree  spreads  out,  and 
the  constant  renewal  of  the  morning  air  in  which 
they  are  suspended,  enables  the  living  plant  to  draw 
an  abundant  supply  for  all  its  wants  from  an  atmos- 
phere already  adjusted  to  the  constitution  of  living 
animals. 

(A  common  lilac  tree,  with  a  million  of  leaves,  has 


246 


ESSAY  ON  CARBONIC  ACID. 


about  400,000,000  of  pores  or  mouths  at  work  suck- 
ing in  carbonic  acid ;  and  on  a  single  oak  tree  as 
many  as  7,000,000  of  leaves  have  been  counted.) 

This  constant  action  of  the  leaves  of  plants  is  one 
of  the  natural  agencies  by  which  the  proportion  of 
carbonic  acid  in  the  lower  regions  of  the  atmosphere 
is  rendered  less  than  it  is  in  the  higher  regions. 

As  water  readily  takes  up  this  gas,  so  it  may  be 
made  by  pressure  to  absorb  a  large  quantity  of  it,  so 
is  the  soda  water  of  the  shops,  and  such  is  also  found 
in  the  bowels  of  the  earth,  as  the  mineral  springs  of  all 
countries  which  contain  also  small  quantities  of  saline 
matters. 

Carbonic  acid  has  been  reduced  from  a  state  of  gas 
into  that  of  liquid  by  compression,  Faraday  obtained 
it  in  this  form,  by  disengaging  it  from  carbonate  of 
ammonia  by  means  of  sulphuric  acid  in  a  glass  tube 
hermetically  sealed,  one  end  of  which  was  immersed 
in  a  freezing  mixture,  and  the  pressure  under  which 
the  fluid  was  formed  was  estimated  to  be  equal  to 
36  atmospheres. 

Carbonic  acid  may  be  decomposed  by  the  action  of 
the  metal  potassium,  which  having  a  stronger  attrac- 
tion for  oxygen  than  the  carbon  has,  when  heated 
in  carbonic  acid,  it  forms  with  great  splendor, 
charcoal  is  deposited  and  an  oxide  of  potassium  is 
formed.  It  may  also  be  decomposed  by  hydrogen 
and  other  bodies. 


ESSAY  ON  CARBONIC  ACID.  24T 

It  is  one-balf  heavier  than  commou  air.  A  con- 
stituent of  our  atmosphere,  which  is  known  to  con- 
sist, in  100  gallons,  of  79  gallons  of  nitrogen  and  21 
gallons  of  oxygen,  while  the  carbonic  acid  is  in  very 
small  proportion. 

At  ordinary  elevations,  there  are  only  about  two 
gallons  of  carbonic  acid  gas  in  5,000  gallons  of  air,  or 
1-2500  part  of  the  whole.  It  increases,  however,  as- 
we  ascend,  so  that  at  heights  of  8,000  or  10^000  feet^ 
the  proportion  of  carbonic  acid  is  nearly  doubled. 
Even  this  increased  quantity  is  very  small,  and  yet 
its  presence  is  essential  to  the  existence  of  vegetable 
life  on  the  surface  of  the  earth.  This  dependance  ap- 
pears  more  striking  the  more  precise  our  ideas  be- 
come as  to  the  absolute  quantity  of  the  carbonic  acid 
which  the  entire  air  contains.  The  whole  weight  of 
the  atmosphere  is  about  fifteen  pounds  to  the  square 
inch,  and  at  this  the  carbonic  forms  somewhat  less 
than  120  grains,  containing  about  33  grains  of  car- 
bon. Notwithstanding  plants  are  continually  suck- 
ing in  this  gas  by  their  leaves,  and  the  operation 
goes  on  so  rapidly,  that  were  the  entire  surface  of 
the  earth  dry  land,  and  under  cultivation,  crops  as 
we  generally  reap  from  it,  would  contract  and  fix  the 
whole  of  the  carbon  in  the  form  of  vegetable  matters 
in  the  short  space  of  twenty-two  years.  Were  this  to 
happen,  vegetation  would  cease.  Such  a  catastrophe 
is  prevented  by  the  constant  restoration  of  carbonic 


ESSAY  ON  CAEBONIC  ACID. 


acid  to  the  air  through  the  increasing  operation  of 
preservation  causes,  which  may  be  summed  up  under 
the  following  heads : 

1.  The  trees  of  the  forest  yearly  shed  their  leaves, 
and,  in  some  countries,  their  bark.  Through  the  in- 
fluence of  the  weather,  these  waste  portions  decay 
and  disappear,  restoring  again  to  the  atmosphere  a 
portion  of  the  same  carbon  which  the  living  tree  had 
previously  detracted  from  it  during  the  period  of 
their  growth.  The  yearly  ripening  herbage,  also, 
and  every  plant  that  naturally  withers  on  plain  or 
liill,  the  grass  of  the  burning  prairie,  and  the  timber 
of  inflamed  forests,  with  all  that  man  consumes  for 
fuel  and  burns  for  other  uses,  every  form  of  vegetable 
XQatter,  in  short,  when  exposed  to  the  action  of  air  or 
fire,  returns  more  or  less  quickly  to  the  state  of  car- 
bonic acid,  and  disappears  in  the  invisible  atmos- 
phere. Thus  what  is  yearly  withdrawn  from  the  air 
by  living  plants  is  so  far  restored  again  by  those 
which  naturally  perish,  or  which  are  destroyed  by 
the  intervention  of  man. 

2.  But  man  himself  and  other  animals  assist  in  the 
same  chemical  conversion.  They  consume  vegetable 
food  with  the  same  final  result  as  when  it  perishes  by 
natural  decay  or  is  destroyed  by  the  agency  of  fire. 
It  is  conveyed  into  the  stomach  in  the  form  in  which 
the  plant  yields  it.  The  green  herb,  the  perfect  seed, 
and  the  ripe  fruit  are  eaten  and  digested.  Then 


ESSAY  ON  CARBONIC  ACID.  249" 

forthwith  they  are  breathed  out  again  from  the  lungs= 
and  skin  in  the  form  of  carbonic  acid  and  water^ 
Let  us  follow  the  operation  more  closely. 

The  leaf  of  the  living  plant  sucks  in  carbonic  acid 
from  the  air,  and  gives  off  the  oxygen  contained  in 
this  gas.  It  retains  only  the  carbon.  The  roots 
drink  in  water  from  the  soil,  and  out  of  this  carbon 
and  water,  the  plant  forms  starch,  sugar,  and: 
other  substances.  The  animal  introduces  this  starch 
sugar  into  its  stomach,  and  draws  in  oxygen 
from  the  atmospliere  by  its  lungs.  With  these  mate- 
rials it  undoes  the  previous  labor  of  the  living  plant,, 
delivering  back  again  from  the  lungs  and  the  skin 
both  the  starch  and  the  oxygon  in  the  form  of  car- 
bonic acid  and  water.  The  circle  begins  with  car- 
bonic acid  and  water,  and  ends  with  the  same  sub- 
stances, the  same  materials.  The  same  carbon,  for 
example,  circulates  over  and  over  again,  now  float- 
ing  in  the  invisible  air,  now  forming  the  substance  of 
the  growing  plant,  now  of  the  moving  animal,  and 
now  again  dissolving  into  the  air,  ready  to  begin 
anew  the  same  endless  revolution.  It  forms  part  of 
a  vegetable  to-day,  it  may  be  built  into  the  body  of 
a  man  to-morrow,  and  a  week  hence  it  may  have 
passed  through  another  plant  into  another  animal. 
What  is  mine  this  week  is  yours  the  next.  There  is, 
in  truth,  no  private  property  in  ever-moving  matters^ 

3.  Yet  all  the  carbonic  acid  which  is  removed  from 


^50 


ESSAY  ON  CARBONIC  ACID. 


the  air  by  the  agency  of  plants  is  not  immediately 
restored  by  the  circulation  above  described.  Two 
larger  wheels  revolve  to  make  up  the  deficiency. 

4.  It  has  been  shown  that  when  plants  die  and 
decay,  are  burned  in  the  air,  or  are  eaten  by  animals, 
the  carbon  they  contain  is  delivered  back  again  to 
the  atmosphere  in  the  form  of  carbonic  acid.  But  all 
the  plants  produced  yearly  over  the  whole  earth  are 
not  so  resolved  into  gaseous  substances  in  any  given 
time.  In  all  parts  of  the  world,  and  during  all  time, 
some  portions  of  vegetable  matter  have  escaped  this 
total  destruction,  and  have  been  buried  beneath  the 
surface  of  the  earth  to  be  preserved  in  the  solid  form 
for  an  indefinite  period.  With  such  comparatively 
indestructible  forms  of  vegetable  matters  we  are  fami- 
liar, in  the  peat  bogs  of  Scotland  and  Ireland,  some- 
times from  50  to  100  feet  deep,  and  in  the  submarine 
forests  which  are  seen  in  so  many  parts  of  our  inland 
shores.  We  are  still  better  acquainted  with  them, 
however,  in  the  vast  deposits  of  coal  which  a  kind 
Providence  long  ago  brought  together  and  covered 
up.  What  is  and  has  been  thus  collected  and  gradu- 
ally buried  would  necessarily  cause  a  constant  dimi- 
nution in  the  small  quantity  of  carbonic  acid  con- 
tained in  the  air  were  there  no  natural  means  in 
operation  for  making  up  the  yearly  loss.  The  means 
we  are  most  familiar  with  for  repairing  this  loss  are 
those  which  man  himself  brings  into  operation.  At 


ESSAY  ON  CARBONIC  ACID. 


^51 


a  certain  period  in  his  history,  half-civilized  man  dis- 
covered the  use  of  coal.  At  a  more  advanced  period, 
he  found  out  how  to  dig  deep  and  hollow  out  mines 
in  search  of  it ;  and  at  a  still  later  period,  how  to  em- 
ploy it  for  a  thousand  beneticial  purposes.  In  burn- 
ing coal,  we  cause  its  carbon  to  unite  with  the  oxygen 
of  the  air,  and  to  disappear  in  the  state  of  carbonic 
acid. 

We  restore  it  to  the  atmosphere  again  in  the  state 
in  which  it  existed  there,  perhaps,  a  million  of  years 
ago,  when  it  was  sucked  in  by  the  growing  plants, 
and,  in  the  form  of  vegetable  matter,  afterwards 
buried  beneath  the  earth's  surface.  In  raising  and 
consuming  coal,  therefore,  we  are,  to  a  certain  extent, 
undoing  and  counteracting  the  -yearly  lessening  of 
the  carbon,  in  the  air,  which  appears  to  come  from 
the  yearly  covering  up  of  a  portion  of  vegetable  mat- 
ter. The  200,000,000  tons  of  coal  which  are  now 
yearly  consumed  throughout  the  globe,  produce  about 
600,000,000  of  tons  of  carbonic  acid.  How  far  this 
quantity  serves  to  compensate  for  what  is  constantly 
buried  up  agaiu,  it  is  impossible  to  estimate.  It 
must  be  acknowledged,  however,  that  the  coal  fires 
we  burn  are  an  important  subsidiary  agent  in  pro- 
moting the  circulation  of  carbon  on  the  globe. 

5.  Again,  within  the  bosom  of  the  great  seas  tiny 
insects  are  at  work,  upon  which  nature  has  imposed, 
in  addition  to  the  search  for  food  and  the  care  of 


352 


ESSAY  ON  CARBONIC  ACID. 


their  offspring,  the  perpetual  labor  of  building  new 
houses.  The  common  shell-iish  of  our  coasts  toil  con- 
tinually for  defence  as  well  as  for  shelter,  rep  airings 
enlarging  and  renewing  their  own  dwelling  places; 
and  as  they  die,  each  drops  its  shell  as  a  feeble  con- 
tribution to  the  beds  of  shelly  limestone,  which  are 
everywhere  forming  at  the  bottom  of  our  deep  seas. 
In  more  southern  waters,  again,  still  humbler  insects- 
build  up  massive  coral  walls,  thousands  of  miles  in 
extent,  which  now  skirting  along  coast  lines,  and 
now  encircling  solitary  islands,  bid  defiance  to  the 
angriest  storms.  And  then,  too,  as  they  die,  genera- 
tion after  generation,  leave  in  rocky  beds  of  coralline 
limestone  an  imperishable  momorial  of  their  exhaust- 
less  labors.  These  rocks  contain,  chained  down  in 
a  seemingly  everlasting  imprisonment,  two-fifths  of 
their  weight  of  carbonic  acid.  This  has  been  all 
withdrawn,  either  directly  or  indirectly,  from  the  at- 
mosphere, and  thus,  through  the  rock,  forming  living 
things  it  contains,  the  sea  must  ever  be  drinking  in 
and  storing  up  the  carbonic  acid  of  the  air. 

The  same  process  has  been  going  on  almost  con- 
tinuously since  the  world  began.  Yast  coral  reefa 
lie  buried  beneath  our  beds  of  coal  and  mountains  of 
thick  ribbed  shelly  limestone  have  been  lifted  from 
ancient  seas  before  these  other  reefs  were  formed. 
The  labours  of  marine  animals,  therefore,  like  the 
burying  of  vegetable  matter  must  throughout  all 


ESSAY  ON  CARBONIC  ACID.  253 

time  have  been  causing  a  daily  lessening  of  the  ab- 
solute quantity  of  carbonic  acid  in  the  atmosphere, 
which  some  other  natural  operation  has  meanwhile 
been  making  compensation  for  this  constant  removal. 
But  the  earth  herself  breathes  for  this  purpose.  From 
cracks  and  fissures,  which  occur  in  vast  nnmbers  over 
the  surface  of  the  earth,  carbonic  acid  issues  in  large 
quantities,  sometimes  alone  and  sometimes  along  with 
springing  waters,  and  daily  mingles  itself  with  the 
ambient  air.  It  sparkles  in  the  springs  of  Carlsbad 
and  Selzer,  rushes  as  if  from  subterranean  bellows 
on  the  table  land  of  Paderborn,  astonishes  travellers 
in  the  Grotto  del  cane,  interests  the  geologist  in  the 
caves  of  Pyrmont  and  among  the  old  caves  of  the 
Eifel  and  is  terrible  to  man  and  beast  in  the  fatal 
"  Yalley  of  Death",  the  most  wonderful  of  the  wonders 
of  Java,  and  besides,  it  doubtless  issues  still  more 
abundantly  from  the  unknown  bottom  of  the  expand- 
ed waters  which  occupy  so  large  a  proportion  of  the 
surface  of  the  globe.  From  these  many  sources,  con- 
tinually flowing  into  the  sea,  carbonic  acid  is  and  has 
been  daily  supplied  in  place  of  that,  which  is  daily 
withdrawn  to  be  buried  in  the  solid  limestones  of  the 
globe.  Did  we  know  after  what  lapse  of  time  the 
earth  would  again  breathe  out  what  is  thus  daily  en- 
tombed, we  should  be  able  to  express  in  words  how 
long  this  slovely  revolving  secular  wheel  requires 
fully  to  perform  one  of  its  immense  gyrations. 

11 


254: 


ESSAY  ON  CARBONIC  ACID. 


Carbonic  acid  gas  rises  from  the  earth  in  an  elastic 
form,  or  assumes  many  successive  varieties  of  plant  and 
animal  forms,  is  finally  buried  in  the  earth  again  in  a 
state  of  blackened  fossil  plants  or  beds  of  solid  lime- 
stone. 

Carbonic  acid,  as  has  already  been  stated,  is  very 
plentifully  disengaged  from  springs  in  almost  all 
countries.  (The  writer  drank,  in  California,  in  a 
fissure  of  the  celebrated  marble  quarry  at  Suisan 
City,  1,000  feet  above  the  level,  ten  cups  of  water, 
in  which  the  carbonic  acid  gas  was  so  abundant  and 
free  that  the  water  was  unable  to  take  up  any  more.) 
It  is,  however,  particularly  abundant  near  active  or 
extinct  volcanoes.  This  elastic  fluid  has  the  property 
of  decomposing  many  of  the  hardest  rocks  with  which 
it  comes  in  contact,  particularly  that  numerous  class 
in  the  composition  of  which  felspar  is  an  ingredient.  It 
renders  the  oxide  of  iron  soluble  in  water,  and  con- 
tributes to  the  solution  of  calcareous  matter.  In  vol- 
canic districts  these  gaseous  emanations  are  not  con- 
fined to  springs,  but  rise  up  in  the  state  of  pure  gas 
from  the  soil  in  various  places,  as  already  observed 
in  the  Grotto  del  Cane,  near  Naples,  and  the  prodi- 
gious quantities  now  annually  disengaging  from  many 
parts  of  the  Limagna  d'Auvergne,  where  it  appears 
to  have  been  developed  in  equal  quantity  from  time 
immemorial.  As  the  acid  is  invisible,  it  is  not  ob- 
served except  an  excavation  be  made,  wherein  it  im- 


ESSAY  ON  CARBONIC  ACID. 


255 


mediately  accumulates,  so  that  it  will  extinguish  a 
candle.  There  are  some  springs  in  this  district  where 
the  water  is  seen  bubbling  and  boiling  up  with  much 
noise  in  consequence  of  the  abundant  disengagement 
of  this  gas.  The  whole  vegetation  is  affected,  and 
many  trees,  such  as  walnut,  flourish  more  luxuriantly 
than  they  would  otherwise  do  in  the  same  soil  and 
climate,  the  leaves  no  doubt  absorbing  the  carbonic 
acid.  It  is  found  in  springs  rising  through  the 
granite  near  CI  aremont,  as  well  as  in  the  tertiary  lime- 
stone of  the  Limagne. 

Near  Claremont,  a  rock  belonging  to  the  gneiss  for- 
mation in  which  lead  mines  are  w^orked,  has  been 
found  to  be  quite  saturated  with  carbonic  acid  gas, 
which  is  constantly  disengaged.  The  carbonates  of 
iron,  lime  and  manganese  are  so  dissolved  that  the 
rock  is  rendered  soft  and  the  quartz  alone  remains 
nnattacked.  Not  far  off  is  the  small  volcanic  cone 
of  Chaluzet,  which  once  broke  up  through  the  gneiss 
and  sent  forth  a  lava  stream. 

The  effect  of  carbonic  acid  as  a.  chemical  agent, 
both  as  commonly  present  in  atmospheric  air  and  as 
more  abundantly  occurring  in  such  localities  as  those 
above  described,  must  depend  on  the  nature  of  the 
rocks  and  other  bodies  with  which  it  may  come  in 
contact.  It  may  thus  cause  the  decomposition  of 
granite,  gneiss,  and  other  feldpathic  and  micaceous 
substances  by  combining  with  the  potash,  soda  and 


256 


ESSAY  ON  CARBONIC  ACIJ>. 


lithia  which  enter  into  their  constitution.  On  the 
contrary,  when  it  encounters  lime  or  magnesia  it 
may  contribute  to  the  production  of  new  rocks. 

The  disintegration  of  granite  is  a  striking  feature 
of  large  districts  in  Auvergne,  especially  in  the  neigh- 
borhood of  Claremont.  Dolomieu  called  this  decay 
"  la  malady  du  granite,"  and  the  rock  may  with  pro- 
priety be  said  to  have  the  rot,  for  it  crumbles  to 
pieces  in  the  hand.  The  phonomenon  may,  without 
doubt,  be  ascribed  to  the  continual  disengagement  of 
carbonic  acid  gas  from  numerous  fissures.  The 
chemical  action  of  carbonic  acid,  as  it  exists  in  the 
usual  state  of  the  atmosphere  near  the  earth's  sur- 
face, though  much  more  gradual,  and,  therefore,  less 
noticed  than  were  it  copiously  evolved  from  the 
water  or  soil  as  in  volcanic  countries,  is  yet  suffici- 
ently powerful  to  produce  a  manifest  effect  on  the 
structure  of  large  masses  of  granite  and  rocks  of 
analogous  composition.  In  the  western  parts  of 
Great  Britain,  where  primitive  formations  prevail^ 
granite  masses  frequently  occur,  which,  from  their 
peculiar  forms,  received  the  celto  Cymric  appellations 
af  lagon,  talmon  and  kistoaers,  and  were  by  the  an- 
tiquarians long  regarded  as  works  of  art  of  Druidical 
origin;  bat  there  rocking  stones,  rock  basins,  cheese- 
rings,  and  altars  are  now  generally  admitted  to  be 
blocks  of  granite  which  have  acquired  their  respective 
forms  in  consequence  of  superficial  decomposition  or 


ESSAY  ON  CARBONIC  ACID. 


25T 


disintegration.  Devonshire  is  the  locality  for  these 
odd  figures,  which,  Dela  Beche  remarked,  looked 
more  like  the  remains  of  some  huge  building  or 
hattlement  than  the  effect  of  cleavage  and  decompo" 
sition,  which  it  is. 

Granite  is  not  generally  regarded  as  a  stratified 
rock,  like  gneiss  and  mica  slate ;  but  it  is  a  fact  well 
known  to  the  workmen  who  are  employed  in  quarry- 
ing and  cutting  it,  that  it  has  what  they  term  a  grain^ 
or  that  it  will  split  in  one  or  more  directions  more 
easily  than  in  others.  This,  doubtless,  is  owing  to 
the  arrangement  of  the  mineral  bodies  of  which  it  is 
composed,  and  especially  the  feldspar,  the  decompo- 
sition of  which  must  essentially  aid  the  process  of 
disintegration,  and  determine  in  a  great  degree  the 
direction  in  which  it  takes  place. 

The  protracted  action  of  atmospheric  air,  and  also 
of  water,  appear  to  act  jointly  as  a  destructive  and 
formative  or  constructive  power ;  likewise  the  more 
rapid  and  violent  operation  of  streams  and  torrenta 
assist  in  dissolving  and  wearing  away  solid  surfaces 
in  the  situation,  and  depositing  beds  of  transported 
matter  in  another  ;  and  the  detritus  of  rocks  and  of 
organic  bodies  have  been  removed  by  the  agency  of 
water  from  the  higher  parts  of  a  country,  and  serving 
to  form  new  tracts  of  land.  Such  catastrophas  are 
common  to  most  countries,  and  if  a  rock  so  detached 
or  weathered  be  limestone,  there  is  not  unfrequently 


« 


258 


ESSAY  ON  CARBONIC  ACID. 


a  reconsolidation  of  the  parts  l^y  means  of  calcareous 
matter  deposited  by  the  water  that  percolates  through 
the  fragments,  and  which  dissolves  a  portion  of  them. 
At  Nice,  the  fractured  surface  thus  reunited  is  so 
hard,  that  if  it  occur  on  a  line  of  road,  it  must  be 
blasted  by  gunpowder  for  removal.  The  same  recon- 
solidation gives  ample  example  upon  the  limestone 
hills  of  Jamaica,  and  at  the  cliffs  of  Milk  river  at 
that  place. 

The  feldpar  contained  in  granite  is  often  easily  de- 
composed, and  when  this  is  effected,  the  surface  fre- 
quently presents  a  quartzose  gravel.  D'Aubuisson 
mentions  that  in  a  hollow  way  which  had  been  only 
Bix  years  blasted  through  granite,  the  rock  was  en- 
tirely decomposed  to  the  depth  of  three  inches,  and 
the  granite  country  of  Auvergne  and  Eastern 
Pyrenees,  felspar  is  frequently  so  much  decomposed 
that  the  traveller  may  imagine  himself  on  large 
tracts  of  gravel.  The  most  striking  example  of  the 
detrition  of  solid  rock  by  the  agency  of  water  is  ex- 
hibited at  the  Falls  of  Niagara.  The  water  at  these 
falls  is  divided  by  a  small  island,  which  separates 
the  river  into  two  cataracts,  one  of  which  is  600 
yards,  and  the  other  Y50  yards  wide.  The  height  of 
the  fall  is  from  150  to  160  feet.  It  is  estimated  that 
670,000  tons  of  water  are  dashed  with  inconceivable 
force  against  the  bottom,  wearing  down  the  adjacent 
rocks.    Since  the  banks  of  the  cataract  were  in- 


ESSAY  ON  CARBONIC  ACID. 


269 


habited  by  Europeans,  they  have  observed  that  it  is 
progressively  shortening  the  distance  of  the  falls  from 
Lake  Erie.  When  it  has  worn  down  the  intervening 
calcareous  rocks,  the  upper  lake  will  'become  dry 
land,  and  form  one  extensive  plain  or  valley,  sur- 
rounded by  rising  ground,  and  watered  by  a  river  or 
small  lake,  which  will  occupy  the  lowest  part.  In 
this  plain,  future  geologists  may  trace  successive 
strata  of  fresh  water  formation  covering  the  subjacent 
ancient  limestone.  The  gradual  deposition  of  minute 
earthy  particles,  or  the  more  rapid  subsidence  of 
mud  from  sudden  inundations,  will  form  distinct  beds 
in  which  will  be  found  the  remains  of  fresh  water 
fish,  vegetables  and  quadrupeds.  Prof.  Henry  says : 
"  The  descent  of  the  country  from  Lake  Erie  to  On- 
tario is  principally  by  a  step,  not  at  the  falls,  but  at 
Lewistown,  several  miles  below.  In  reviewing  the 
position  of  the  Falls,  and  the  features  of  the  country 
around,  it  is  impossible  not  to  be  impressed  with  the 
idea  that  this  great  natural  race-way  has  been  formed 
by  the  continued  action  of  the  irresistable  current  of 
the  Niagara,  and  that  the  falls,  beginning  at  Lewis- 
ton,  have,  in  the  course  of  ages,  worn  back  the  rocky 
strata  to  their  present  site.  The  deep  chasm  through 
which  the  Niagara  passes  below  the  falls  is  nearly  a 
mile  wide,  with  almost  perfect  mutual  sides.  The 
bed  of  the  river  below  the  falls  is  strewed  with  huge 
fragments  of  rocks  hurled  down  by  the  cataract. 


'260 


ESSAY  ON  CARBONIC  ACID. 


The  retrogration  of  the  waterfall,  owing  to  the  de- 
struction of  the  surface  over  which  it  takes  its  course, 
is  said  to  have  amounted  to  nearly  fifty  yards  during 
the  last  forty  years.  If  the  excavation  always  pro- 
ceeded at  the  same  rate,  it  must  have  required  about 
10,000  years  for  the  formation  of  the  whole  ravine  ; 
and  it  would  take  up  more  than  30,000  years  from 
the  present  time  before  the  channel  would  be  worn 
backward  to  Lake  Erie ;  but  if  it  retroceded  1  inch 
a  year,  which  would  make  8f  feet  a  century,  380,000 
years." 

The  great  gorge  of  the  Colorado,  which  is  300 
miles  long  and  3-6000  feet  deep,  and  hundreds  of 
feet  of  the  depth  being  much  of  the  distance  through 
granite,  has  probably  taken  the  same  length  of  time 
as  the  Niagara  retrocession,  and  at  the  close  of  the 
mesozoic  period  or  reptilian  age,  which  was  the  era 
of  the  culmination  and  incipient  decline  of  two  great 
types  in  the  animal  kingdom,  the  reptilian  and  mol- 
luscan,  and  remarkable  as  the  era  of  the  first 
mamals,  birds  and  fishes. 

Before  proceeding  further  of  the  functions  of  car- 
bonic acid  in  the  inorganic  world,  let  us  make  a  few 
remarks  respecting  the  distinctions  between  animals 
and  plants,  in  order  to  show  how  near  the  organic 
bodies  are  related  to  the  inorganic,  and  that  carbonic 
acid  may  probably  have  an  important  agency  in  this 
all  important  work.    Since  the  discovery  that  the 


ESSAY  ON  CARBONIC  ACID. 


261 


spores  (or  seed  cells)  of  some  algae  have  locomotion 
like  animalcules,  and  that  there  are  unicellular  loco- 
motive plants  (the  diatoms,  etc.)  Some  have  thought 
that  the  two  kingdoms  of  life  were  blended  together 
through  their  inferior  species.  But  the  fact  is  that 
they  are  diverse  throughout ;  the  opposite  but  mutu- 
ally dependent  sides  or  parts  of  one  system  of  life. 
The  following  are  some  of  their  distinctions  : 

1.  Plants  excrete  oxygen,  a  gas  essential  to  animal 
life ;  animals  excrete,  in  respiration,  carbonic  acid,  a 
gas  essential  to  vegetable  life. 

2.  Plants  take  inorganic  material  as  food  and  turn 
it  into  organic ;  animals  take  this  organic  material 
thus  prepared  (plants)  or  other  organic  materials 
made  from  it  (animals),  finding  no  nutriment  in  in- 
organic matter. 

3.  Plants  passing  from  the  unicellular  state  by 
growth  lose  in  power,  becoming  usually  fixed ;  ani- 
mals, in  the  same  change  or  in  development  from  a 
germ,  increase  in  power,  augmenting  in  muscular 
force ;  and  also  in  the  case  of  species  above  the  low- 
est grade  in  nervous  force,  like  an  ant  is  a  one  ant- 
power,  a  horse  a  one  horse-power,  whence  an  animal 
is  a  self-propogating  piece  of  enginery,  of  various 
power,  according  to  the  species. 

4.  The  vegetable  kingdom  is  a  provision  for  the 
storing  away  or  magazining  of  force  for  the  animal 
kingdom.    This  force  is  acquired  through  the  sun's 


262 


ESSAY  ON  CARBONIC  ACID. 


influence  or  forces  acting  on  the  plant,  and  so  pro- 
moting growth.  That  of  starch,  vegetable  fibre  and 
sugar  is  a  state  of  concentrated  or  accumulated  force^ 
and  there  is  also  a  magazining  of  force  in  a  still  more 
concentrated  or  condensed  state.  There  are  thus  five 
states  of  stored  force  in  nature — three  in  inorganic, 
the  solid^  liquid  and  gaseous  ;  and  two  in  organic, 
the  vegetable  and  animal.  The  animal  type  diff'ers 
from  the  vegetable,  (though  not  all  animals  from 
plants,)  in  this,  that  while  the  latter  has  the  superior 
and  inferior  polarity  of  single  growth — the  stem  grow- 
ing upward  and  the  root  downward — the  former  has 
the  anterior  and  posterior  or  cephalic  and  aiiticephalic 
polarity  connected  with  a  well  developed  nervous 
system..  The  radiates  among  animals  are  allied  in 
this  respect  to  plants,  being  animal  representatives 
of  the  vegetable  radiate  type  ;  and  this  is  the  ground 
of  the  subdivision  of  the  animal  kingdom. 

The  following  are  the  two  grand  subdivisions  in 
groups  in  nature,  the  first  mentioned  being  the  infe- 
rior, the  other  the  superior.  The  latter  is  also  the 
more  typical  group,  or  that  in  which  the  idea  of  the 
type  is  more  fully  represented  : 

a.  Life  in  general — 1,  vegetable;  2,  animal  king- 
dom. 

h.  Vegetable  kingdom — 1,  cryptogams  or  flowerless 

plants ;  2,  phanerogams  or  flowering  plants. 
c.  Animal  kingdom — 1,  the  flower-like  type,  in- 


ESSAY  ON  CARBONIC  ACID. 


263 


eluding  radiates;  2,  the  true  animal  type  or 
cephalized  species,  that  is,  those  having  a 
head  or  anterior  and  posterior  polarity  with 
bilateral  symmetry,  including  mollosks,  arti- 
culates and  vertebrates. 

d.  Sub-kingdom  of  mollusks — 1,  the  flower-like 

type,  including  the  bryozoans  closely  like 
flowers,  the  brachiopods  generally  attached 
by  stem  or  pedicles,  and  ascidiaiis,  also  often 
attached ;  2,  the  true  molluscan  type,  includ- 
ing acephals,  cephalates  and  cephalopods. 

e.  Sub-kingdom   of  yertebrates — 1,  water  verte- 

brates, including  tishes ;  2,  land  vertebrates, 
including  reptiles,  birds  and  animals. 

f.  Class  of  crustaceons — 1,  entomostroceons ;  2, 

raalacostroceons. 

g.  Class  of  reptiles — 1,  amphibious;  2,  true  rep- 

tiles. 

A.  Class  of  mammals — 1,  marsupials  or  semiovipar- 
ans  ;  2,  nonmarsuphial  or  typical  mammals. 

The  great  question  of  the  day  is,  where  can  we 
draw  a  strait  line  between  organic  and  inorganic 
bodies,  for  if  we  ever  succeed  to  produce  these 
organic  matters,  fat,  starch,  or  tibrine  from  inor- 
ganic substances,  the  problem  would  be  solved. 

From  a  lecture  by  Dr.  Loew,  of  the  College  of  the 
City  of  New  York,  referring  to  this  great  difficulty, 
and  to  the  important  place  carbonic  acid  assumes  in 


264 


ESSAY  ON  CARBONIC  ACID. 


the  organisms,  the  followmg  extract  must  be  highly 
interesting : 

"  Confessing  that  we  cannot  state  positively  how 
-the  first  organic  being  was  formed  from  inorganic 
matter,  nevertheless  we  must  conclude  from  conse- 
quence that  it  ^vas  formed  by  natural  forces. 
When  we  see  that  the  vegetable  can  produce  organic 
matter  from  inorganic  substance ;  when  we  see  the 
animal  being  taking  this  organic  matter  of  the  vege- 
table up,  and  during  the  process  of  its  life  connecting 
in  the  very  same  inorganic  combinations  from  which 
the  vegetable  builds  up  its  body ;  when  we  see  this 
inlinite  construction,  destruction,  and  reconstruction, 
we  remark,  as  one  of  the  first  conditions,  that  the 
vegetable  world  existed  previous  to  the  animal  world. 
Hence  arises  the  question.  How  was  the  first  organ- 
ized vegetable  world  formed  ?  There  are  possibilities 
directly  from  inorganic  matter  or  from  previously 
formed  organic  matter.  Above  all,  let  me  ask  here 
attention  to  the  difierence  between  the  words  '  or- 
ganic '  and  '  organized.'  The  chief  part  of  an  organ- 
ism consists  of  carbon,  hydrogen,  oxygen,  and  nitro- 
gen ;  water  and  mineral  salts  form  the  remainder. 
These  four  most  important  elements  combine  in  an 
infinite  number  of  proportions,  and  these  combina- 
tions are  of  such  an  extremely  complex  order  as  are 
never  to  be  found  in  the  inorganic  world.  An  or- 
ganic combination  is  the  first  condition  for  an  organ- 


ESSAY  ON  CARBONIC  ACID. 


265 


ized  body,  and  organic  combinations  form  the  step 
from  inorganic  matter  to  organized  beings.  Two 
possibilities  may  have  existed :  either  organic  matter 
was  formed  from  inorganic  by  natural  forces,  pre- 
vious to  the  formation  of  the  first  cell,  or  in  the  other 
case,  the  cell,  during  its  formation,  formed  also  the 
organic  combination  necessary  for  its  life  from  mine- 
ral salts,  carbonic  acid,  and  water.  In  the  first  case, 
the  spontaneous  generation  has  the  same  plasmogony  ; 
in  the  second,  autogeny.  Theodore  Saussure  was  the 
first  who  stated  the  fact  that  the  carbonic  compounds 
in  the  vegetables  derive  their  carbon  from  the  car- 
bonic acid  contained  in  the  air,  and  their  hydrogen 
from  the  matter.  Liebig  then  stated  that  the  nitro- 
gen of  the  plants  comes  from  the  ammonia  contained 
in  the  soil  and  in  the  atmosphere.  We  see,  there- 
fore, the  body  of  the  vegetable,  no  matter  how  com- 
plicated its  structure  and  its  organization  may  be,  is 
built  up  chiefly  from  carbonic  acid  and  water — three 
inorganic  combinations  of  a  simple  constitution.  By 
a  process  of  reduction,  complicated  organic  radicals 
are  formed,  combining  themselves  to  numerous 
bodies.  Among  these  are  sugar,  fat  and  albumen. 
As  organic  chemistry  must  be  considered  as  an  off- 
spring of  this  century,  it  was,  of  course,  considering 
its  tender  age,  not  possible  until  a  few  decades  ago 
to  prepare  an  organic  body  synthetically  from  its 
€!lements  ;  therefore  the  hypothesis  came  in  vogue 


266 


ESSAY  ON  CARBONIC  ACID. 


that  there  exists  an  especial  power,  the  vital  power.. 
It  was  long  considered  as  an  impossibility  to  prepare 
artificially,  from  inorganic  matter,  such  combinations 
as  may  occur  in  the  vegetable  and  animal  body.  The 
death-knell  of  the  dogma  of  vital  force  was  tolled  in 
the  year  1828.  In  this  year  the  German  chemist^ 
Woehler,  prepared,  synthetically,  the  first  organic 
combination.  Woehler,  in  attempting  to  prepare 
eganate  of  ammonia,  got,  in  evaporating  a  mixture 
of  eganate  of  potassium  and  sulphate  of  ammonia,  a 
body  of  an  entirely  difterent  character  to  the  salt  he 
was  seeking  for.  The  atoms  arranged  themselves  in 
another  form,  and  this  body  presented  itself  exactly 
the  same  as  that  which  is  found  in  animal  urine, 
named  urea.  This  was  the  first  step  on  a  new  road, 
and  so  rapid  was  the  progress  of  organic  chemistry, 
so  rapidly  was  it  advancing,  that  now  we  can  count 
them  by  the  hundreds.  Dr.  Loew  then  gave  instan- 
ces of  some  of  these  combinations.  Thus  hydrogen 
and  carbon,  united  in  the  voltaic  curve,  produce  the 
hydrocarbon  acetyline — the  root  of  numerous  organic 
combinations — until,  with  hydrogen,  it  produces  de- 
fiant gas ;  the  cyanide  of  this  gas,  boiled  with  potassa^ 
gives  succinic  acid  ;  this  treated  with  brimstone,  and 
then  with  potassa,  gives  malic  and  tartaric  acid ;. 
malic  acid  heated  gives  fumaric.  But  malic,  tartaric 
and  fumaric  are  organic  acids  occurring  in  a  great 
number  of  vegetables ;  they  can  thus  be  artificially 


ESSAY  ON  CAKBONIC  ACID. 


26T 


prepared  from  the  elements.  From  acetyline  ben" 
zol  may  be  produced  ;  from  benzol,  benzoic  acid,  the 
root  of  a  great  number  of  organic  combinations^ 
which  can  all  be  artificially  prepared  from  benzoic 
acid,  as  oil  of  bitter  almonds,  gallic  acid,  hypurie 
acid,  &G.  Sulphur  and  carbon  may  be  united;  the 
bisulphide  of  carbon,  treated  with  iron  filings  and 
water,  gives  formic  acid,  which  occurs  in  the  ant  and 
in  the  nettle ;  formic  acid,  treated  with  potassa,  yields- 
oxalic  acid,  which  is  found  in  many  plants.  By  treat- 
ing oxalic  ether  with  sodium  amalgam,  we  obtain 
disoxalic  and  malic  acid  and  a  kind  of  sugar,  all  or- 
ganic substances.  Dr.  Loew  added  to  these  instances- 
numerous  others,  in  which  organic  substances,  such 
as  fat,  sugar,  and  alcoliol,  were  formed  by  chemical 
processes  from  inorganic  bodies.  He  then  continued : 
These  organic  bodies  which  I  have  mentioned  here 
form  only  a  small  part  of  the  numerous  organic  com- 
binations which  can  be  prepared  artificially  from  the 
elements  in  the  laboratory ;  but,  simultaneously,  I 
must  confess  that  there  is  much  more  to  do  than  has 
been  done.  For  example,  gum-starch,  quinine, 
strychnine,  cannot  yet  be  artificially  prepared,  but 
there  is  not  the  slightest  doubt  that  chemistry  will 
solve  all  these  problems  in  coming  time.  Further,  it 
must  be  mentioned  that  the  ways  of  the  chemist 
in  the  laboratories  are  different  from  the  ways  of 
nature.    The  chemist  has  strong  acids  at  his  disposi- 


^68 


ESSAY  ON  CARBONIC  ACID. 


tion  ;  not  so  with  nature,  for  she  works  only  with  the 
reducing  power  of  the  sunlight.  That  cannot  as  yet 
Be  imitated,  although  we  can  often  reach  the  same 
result  in  a  laboratory.  The  history  of  chemistry, 
however,  bids  us  to  hope  that  this  problem  will  yet 
be  solved.  When  this  great  problem  finds  its  solu- 
tion, we  will  obtain,  probably  some  light,  as  to  how, 
from  carbonic  acid,  water  and  ammonia,  organic 
matter  was  formed  hundreds  of  thousands  of  years 
ago,  when  the  first  cell  became  endowed  with  life. 
In  every  case  we  had  different  conditions  in  those  in- 
finitely remote  ages — conditions  more  favorable  for 
spontaneous  generation,  as  there  was  a  very  warm 
and  wet  atmosphere  rich  in  carbonic  acid,  with  a 
mineral  surface  more  liable  to  change,  and  different 
in  appearance  to  what  it  is  now-a-days.  Therefore, 
it  is  probable  that  those  first  cells  had  quite  a  differ- 
ent charactsr,  as  we  imagine  very  liable  to  change 
and  to  different  developments.  Many  experiments 
have  been  made  to  produce,  artificially,  cells,  infuso- 
ries,  or  fungi,  and  this  question  seems  to  be  satisfac- 
torily solved." 

In  regard  to  the  chemical  relations  of  our  globe,  Dr. 
T.  Sterry  Hunt,  in  his  lecture  on  primeval  chemis- 
try, throws  much  light  on  the  functions  of  carbonic 
acid  exercised  upon  our  globe,  and  cannot  do  better 
than  to  make  an  extract  of  his  remarks  : 

After  explaining  the  astronomical  parts  and  solar 


ESSAY  ON  CARBONIC  ACID. 


269 


system,  he  says,  in  reference  to  the  history  of  this 
earth,  that  there  were  no  chemists  who  had  an  eye, 
except  the  eye  of  its  great  All  Seeing  One,  to  inves- 
tigate  the  marvellous  phenomena ;  but  the  chemist  of 
the  present  day  has  to  look  to  the  rocks,  water  and 
air,  and  to  their  origin. 

Our  earth  was  once  a  luminous  mass  of  vapor, 
passing  through  a  stage  in  which  it  was  self-luminous 
like  the  sun,  until  it  finally  became  cool  to  such  a 
point  that  it  liquified  and  became  at  last  solid.  The 
next  question  is,  did  the  earth  become  solid  first  at 
the  circumference  or  at  the  center  ?  This  is  important 
from  more  than  one  point  of  view,  and  has  been  in- 
vestigated by  astronomers,  physicists,  and  chemists, 
and  it  seems  pretty  clearly  proved  that  the  earth,  if 
not  solid  to  the  center,  must  have  a  crust  several 
hundred  miles  in  thickness.  And  it  is  probable  that 
if  the  cooling  commenced  at  the  center,  that  at  least 
the  surface  would  be  covered  with  a  thin  layer  of 
liquid  matter,  which,  on  cooling,  would  give  an  un- 
even surface  to  the  primeval  globe.  So  far  as  the 
chemistry  of  our  planet  is  concerned,  we  have  to  deal 
only  with  this  outer  layer,  all  the  various  elements  of 
which  must  have  existed  either  in  that  crust  or  in  the 
atmosphere  which  then  surrounded  it.  We  form  a 
good  idea  of  this  primeval  crust,  if  we  suppose  the 
elements,  rocks,  air  and  ocean  to  be  brought  together 
at  the  intense  heat  wliich  tlien  existed.    Under  such 


270 


ESSAY  ON  CARBONIC  ACID. 


conditions  the  lime,  magnesia,  alkalies — would  all 
unite  into  combination  with  silica  and  alumina,  while 
the  atmosphere  would  contain  chlorine,  sulphur, 
carbon  and  hydrogen,  together  with  oxygen  and 
nitrogen.  This  would  form  on  the  one  hand  a  slag- 
like siliceous  mass,  and  on  the  other  hand  an 
atmosphere  charged  with  acid  vapors,  yielding  all  the 
chlorine,  sulphur  and  carbon  in  the  form  of  acids,  and 
the  water  in  the  form  of  steam  mixed  w^ith  nitrogen 
and  oxygen.  The  weight  of  the  atmosphere  would 
be  immense,  and  under  its  pressure  water  and  the  less 
volatile  acids  would  be  liquified  at  the  high  tempera- 
ture, and  these  acid  waters  would  collect  in  the  de- 
pressions of  the  earth's  crust,  where  they  would 
immediately  decompose  the  silicates,  separating  the 
silica  and  forming  sulphates  and  chlorates  of  the  al- 
kalies— lime  and  magnesia.  This  solution  would  form 
first,  sea  water,  and  the  action  would  continue  till 
these  affinities  were  satisfied.  Then  commenced  a 
new  chemical  process,  the  action  of  air  and  water 
upon  the  exposed  portions  of  the  earth's  crust,  con- 
verting the  silica  into  clay,  with  carbonates  of  lime, 
magnesia,  and  soda  through  the  action  of  the  carbonic 
acid  of  the  atmosphere.  The  soda  carried  by  rains 
to  the  sea,  decomposes  the  lime  salts,  forming  car- 
bonate of  lime  and  sea  salt.  The  process  is  still  going 
on,  though  more  slowly,  from  the  small  amount  of 
carbonic  acid  in  the  air,  and  causing  the  decay  in  the 


ESSAY  ON  CARBONIC  ACID. 


271 


hearts  of  granite  rocks.  We  have  thus  explained  the 
generation  of  silica  or  quartz  of  elay  and  of  lime- 
stones, the  principle  elements  of  sedimentary  rocks. 
Every  clod  of  clay  represents  granite  rocks  decom- 
posed, and  an  amount  of  limestone  and  sea  salt^ 
formed  from  the  waters  of  the  ocean.  In  this  way 
the  air  was  freed  from  carbonic  acid,  and  fitted  for 
the  support  of  animal  life.  Besides  this,  the  vege- 
tation removed  large  portions  of  carbonic  acid,  re- 
placing it  by  oxygen,  and  the  formation  of  limestone 
directly  diverted  still  greater  amounts  of  carbonic 
acid,  whose  presence  must  have  rendered  the  early 
atmosphere  unfit  for  the  higher  forms  of  life.  The 
presence  of  carbonic  acid  in  the  early  atmosphere 
serves  to  explain  the  higher  temperature  then 
prevailing,  which  permitted  the  growth  of  tropical 
plants  within  polar  circles.  Wc  know  that  a  portion 
of  carbonic  acid,  such  as  then  existed  in  the  air,  while 
it  would  not  prevent  the  passage  of  the  sun's  rays 
would  impede  the  radiation  of  obscure  heat  from  the 
earth's  surface,  and  thus  tend  to  keep  up  a  summer 
temperature.  The  effect  of  this  carbonic  acid  would 
be  like  the  glass  of  an  orchard-house  in  preventing 
the  escape  of  heat.  Thus  carbonic  acid  exerted  also 
an  important  part  in  many  other  chemical  processes; 
then  active  at  the  earth's  surface.  Besides  deposits, 
formed  by  chemical  processes,  mechanical  operations 
were  forming  at  the  earth's  surface  a  great  amount 


ESSAY  ON  CARBONIC  ACID. 


of  sandy  and  clayey  rocks,  which  make  up  the  bulk 
of  the  stratified  forms.  Although  the  interior  of  the 
earth  has  been  regarded  as  solid,  it  is  notwithstanding 
doubtless  intensely  heated,  and  thus  is  explained  the 
increase  of  temperature  as  we  go  below  the  surface. 
The  cooling  of  this  center,  once  rapid,  is  now  very 
slow  indeed  from  the  thickness  of  the  overlying  sedi- 
ment. The  effect  of  this  heat  upon  the  deeply  buried 
sediment  has  been  to  crystallize  them,  and  convert 
them  into  metamorphic  rocks.  To  this  class  belongs 
granite,  once  looked  upon  as  a  primitive  rock.  We 
have  now  evidence  that  granite  is  in  all  cases  a 
secondary  rock,  derived  from  sediments  crystallized 
through  the  agency  of  water  and  heat.  In  the  quartz 
of  granite  are  often  found  small  cavities,  partly  filled 
with  water,  which  are  so  many  small  thermometers 
showing  the  temperature  at  which  the  granite  was 
crystallized.  Pressure,  which  increases  the  melting 
point  of  rock  when  exposed  to  fires,  greatly  favors 
the  dissolving  power  of  heated  water,  so  that  we  may 
suppose  that  the  lowest*  strata  of  sediment  and  often 
adjacent  portions  of  the  primal  nucleus  being  per- 
meated with  water,  under  great  heat  and  pressure, 
became  softened  and  yielding.  From  this  softened 
zone  came  all  eruptive  rocks,  and  in  it  are  to  be 
found  the  causes  of  volcanoes  whose  various  products 
are  generated  by  the  action  of  heat  upon  the  varied 
elements  of  deeply  buried  sedementary  strata.  The 


ESSAY  ON  LIMESTONES. 


2Y3 


theory  which  ascribes  volcanic  products  to  the  sup^ 
posed  uncooled  liquid  center,  fails  entirely  to  account 
for  the  great  diversity  in  composition  of  these  pro- 
ducts, all  of  which,  wherever  found,  are  represented 
in  rocks  of  aqueous  origin.  The  distribution  of 
niodern  vocanoes  shows  them  to  be  intimately  con- 
nected comparatively  recent  accumulations  ot 
sedimentary  rocks  ;  entire  absence  of  volcanic  pheno- 
mena over  the  eastern  part  of  this  continent  is  thus 
explained. 

II.   0?i  Limestones:  their  Origin  and  Functions. 

The  early  geologists  were  impressed  with  the 
theory  of  the  origin  of  all  limestones;  that  is,  was 
due  to  organized  beings  or  substances,  and  the  reason 
advanced  by  them  was  because  the  quantity  of  lime- 
stone in  the  primary  strata  bore  a  much  smaller  pro- 
portion to  the  silicious  and  argillaceous  rock  in  the 
secondary,  and  because  testaceous  animals  were  so 
rarely  found  in  the  ancient  ocean,  and  furthermore 
that  the  quantity  of  calvareous  earth  deposited  in  the 
form  of  mud  or  stone  is  always  increasing,  and  that 
as  the  secondary  series  far  exceeds  the  primary  in 
this  respect,  so  a  third  series  may  hereafter  arise  from 
the  depth  of  the  sea,  which  will  exceed  the  last  in 
the  proportion  of  its  calcaceous  strata.  Some  con- 
clusions were  drawn  from  this  assertion  that  lime 


274 


ESSAY  ON  LIMESTONES. 


may  probably  be  an  animal  product  combined  by  the 
powers  of  vitality  from  some  simple  elements,  and 
that  every  particle  of  lime  that  now  enters  into  the 
crust  of  the  globe,  may  possibly  in  its  turn  have  been 
•subservient  to  the  purposes  of  life  by  entering  into 
the  composition  of  organized  bodies. 

Lime  is  contained  in  the  ocean  and  is  plentifully 
secreted  by  the  testacea  and  corals  of  the  Pacific, 
and  must  have  derived  either  from  springs  rising  up 
in  the  bed  of  the  ocean  or  from  rivers  fed  by  calca- 
reous springs  or  impregnated  with  lime,  derived  from 
-disintegrated  rocks,  both  volcanic  and  hypogene  and 
the  greater  proportion  of  limestone  in  the  more 
modern  formations,  or  compared  to  the  most  ancient 
may  be  explained,  for  springs  in  general  hold  no 
argillaceous  and  but  a  small  quantity  of  siliceous 
matter  in  solution,  but  they  are  continually  substract- 
ing  calcareous  matter  from  the  inferior  rocks.  The 
constant  transfer  therefore  of  carbonate  of  lime  from 
the  lower  or  older  portions  of  the  earths'  crust  to  the 
surface  must  cause  at  all  periods  and  throughout  an 
indefinite  succession  of  geological  epochs  a  prepon- 
derance of  calcareous  matter  in  the  newer  or  con- 
trasted with  the  older  formations.  It  has  been  urged 
that  we  discover  in  the  ancient  rocks  the  signs  of  an 
epoch,  when  the  planet  was  uninhabited  and  when 
its  surface  was  in  a  chaotic  condition.  The  opinion 
however  that  the  oldest  of  the  rocks  now  visible  may 


ESSAY  ON  LIMESTONES. 


2Y5 


be  the  last  monuinents  of  an  antecedent  era  in  which 
living  beings  may  already  have  peopled  the  land  and 
water,  has  been  declared  to  be  equivalent  to  the 
assumption  that  there  never  was  a  beginning  to  the 
present  order  of  things,  no  argument  can  be  drawn 
from  premises  in  favor  of  the  infinity  of  the  space 
that  has  been  filled  with  worlds,  and  if  the  material 
universe  has  any  limits,  it  then  follows,  that  it  must 
occupy  a  minute  and  infinitessimal  point  in  infinite 
space.  So  if  in  tracing  back  the  earth's  history,  we 
arrive  at  the  monuments  of  events  which  may  have 
happened  millions  of  ages  before  our  time,  and  if 
we  still  find  no  decided  evidence  of  a  commence- 
ment, yet  the  arguments  from  analogy  in  support  of 
the  probability  of  a  beginning  remains  unshaken, 
and  if  the  past  elevation  of  the  earth  be  finite,  then 
the  aggregate  of  geological  epochs,  however  numer- 
ous, must  constitute  a  mere  movement  of  the  past,  a 
mere  infinitesimaal  portion  of  eternity! 

We  know  that  it  is  not  only  the  present  condition 
of  the  globe,  which  has  been  suited  to  the  accommo- 
dation of  myriads  of  living  creatures,  but  that  many 
former  states  also  have  been  adapted  to  the  organiza- 
tion and  habits  of  prior  races  of  beings.  The  dispo- 
sition of  the  seas,  continents  and  islands,  and  the 
climates,  have  varied,  the  species  likewise  have  been 
changed  ;  yet  they  have  all  been  so  modelled  on 
types   analogous  to  those  of  existing  plants  and 


276 


ESSAY  ON  LIMESTONES. 


animals,  as  to  indicate  tlirongliout  a  perfect  harmonj 
of  design  and  unity  of  purpose.  To  assume  that  the 
evidence  of  the  beginning  or  end  of  so  vast  a  scheme 
lies  within  the  reach  of  our  philosophical  inquiries, 
or  even  of  our  speculations,  appears  to  be  inconsis- 
tent with  a  just  estimate  of  the  relations  which 
subsist  between -the  Unite  powers  of  man  and  the 
attributes  of  an  infinite  and  eternal  being.  The 
peculiar  position  of  lime  in  the  system  of  nature,  is 
that  of  a  medium  between  the  organic  and  inorganic, 
world.  Carbonate  of  lime  is  soluble  in  water  which 
holds  a  little  carbonic  acid  in  solution,  and  is  found 
in  river,  marine  and  well  waters.  It  is  made  inta 
shells,  corals,  and  partly  into  bone,  by  animals,  and 
then  turned  over  to  the  inorganic  world  to  make 
rocks.  Lime  is  therefore  the  medium  by  which 
organic  beings  aid  in  the  inorganic  progress  of  the 
globe ;  for  the  greater  part  of  limestones  have  been 
made  through  the  agency  of  life,  either  vegetable  or 
animal.  Lime,  which  is  the  oxide  of  the  metal  cal- 
cium, is  commonly  called  quicklime,  forms  com- 
pounds with  silica  or  silicate,  with  carbonic  acid,  the 
carbonate  or  carbonate  of  lime,  which  is  the  material 
of  limestones,  with  sulphuric  acid  the  sulphate  of 
lime  or  gypsum. 

Lime  also  unites  with  phosphoric  acid,  forming 
phosphate  of  lime,  the  essential  material  of  bones,  a 
constituent  also  of  other  animal  tissues.    Like  the 


ESSAY  ON  LIMESTONES.  2^7 

carbonate,  this  phosphate  is  afterwards  contributed 
to  the  rock  material  of  the  globe,  and  is  one  sonrce 
of  mineral  phosphates.  Calcium  is  one  of  the  nine 
elements  which  are  the  prominent  constituents  of 
rocks,  viz.,  oxygen,  silicon,  aluminium,  magnesium, 
calcium,  potassium,  sodium,  and  carbon,  making  up 
977-1000  of  the  whole  crust.  The  limestones  of  the 
giluric  and  later  ages  have  nearly  all  been  made 
through  the  wear  and  accumulation  of  shells,  crinoids 
and  corals,  or  the  calcareous  relics  of  whatever  life 
occupied  the  seas.  The  great  limestone  formations 
of  existing  coral  seas  are  modern  examples  of  the 
process.  It  has  been  the  subject  of  curious  specula- 
tion whence  the  coral  polypifers  and  testaceous 
mollusca  can  obtain  the  vast  quantities  of  carbonate 
of  lime  which  they  secrete  to  form  the  envelopes  by 
which  they  are  preserved.  It  has  been  considered 
more  than  probable  that  they  have  the  extraordinary 
faculty  of  producing  lime  from  simple  elements. 
Some  seem  disposed  to  impute  its  origin  in  the 
same  manner  to  the  influence  of  vital  energy  in 
combining  elementary  bodies^  and  it  follows  that 
the  quantity  of  lime  on  the  surface  of  the  eartli 
must  be  progressively  increasing,  unless  it  be 
supposed  that  other  natural  processes  are  regu- 
larly taking  place  for  the  decomposition  of 
calcareous  earth,  or  rather  of  the  metallic  base 
calcium, 

12 


278 


ESSAY  ON  LIMESTONES. 


Mr.  Lyell,  however,  sees  no  reason  for  supposing 
^that  the  lime  now  on  the  surface  or  in  the  crust  of 
the  earth  may  not,  as  the  silex  and  aluminum,  or 
any  other  mineral  substance,  have  existed  before  the 
first  organic  beings  were  created,  if  it  be  assumed 
that  the  arrangement  of  the  inorganic  materials  of 
our  planet  proceeded  in  the  order  of  time,  the  intro- 
duction of  the  first  organic  inhabitants,  and  adds,  in 
reference  to  the  abundance  of  carbonate  of  lime 
furnished  by  springs  which  rise  through  granite,  that 
if  the  carbonate  of  lime,  secreted  by  the  testaceous 
corals  of  the  Pacific,  be  chiefiy  derived  from  below, 
and  if  it  be  a  very  general  effect  of  the  action  of 
subterranean  heat  to  subtract  calcareous  matters  froai 
the  inferior  rocks,  and  to  cause  it  to  ascend  to  the 
surface,  no  argument  can  be  derived  in  favor  of 
the  unaggressive  increase  of  limestone  from  the  mag- 
nitude of  coral  reefs,  or  the  greater  proportion  of 
calcareous  strata  in  the  more  modern  formations.  A 
constant  transfer  of  carbonate  of  lime  from  the 
inferior  parts  of  the  earth's  crust  to  its  surface,  would 
cause  throughout  all  future  time,  and  for  an  indefinite 
succession  of  geological  epochs,  a  preponderance 
of  calcareous  matter  in  the  newer  as  contrasted 
^ith  the  older  formations. 

The  rock,  formed  under  the  surface  of  the  sea 
originated  either  from  depositions  or  from  chemical 
precipitation ;  those  of  the  former  class  are  numerous, 


ESSAY  ON  LIMESTONES. 


279 


including  most  of  the  stratified  rocks  which  inclose 
ssa-shells,  fragments  of  corals,  and  other  exuviae  of 
bones  of  marine  animals.  Among  those  of  the 
better  class,  some  geologists  have  reckoned  even 
granite,  and  Deluc  states  in  that-  respect  that  the 
strata  of  granite  were  evidently  produced  by  chemi- 
cal decompositions  from  a  liquid,  and  form  the  most 
ancient  monument  of  the  action  of  physical  causes 
on  our  globe ;  however  the  origin  of  granite  as  well 
as  that  of  all  other  unstratitied  rocks,  has  been 
ascribed  mostly  to  igneous  fusion  and  consolidation. 
Most  of  the  calcareous  rocks  containing  marine  shells 
must  have  been  produced  under  the  influence  of 
chemical  affinity,  and  of  this  nature  are  the  forma- 
tions which  are  occasionally  observed  to  take  place 
on  the  sea  coasts.  Collections  of  perfect  and  broken 
shells  and  corals  are  sometimes  consolidated  by  the 
precipitation  of  calcareous  and  ferruginous  matter, 
constituting  banks  or  beds  of  considerable  extent. 
Such  masses,  containing  shells,  occur  in  various  parts 
of  the  shores  of  Great  Britain.  Similar  conglome- 
rates, including  both  shells  and  corals,  are  not  uncom- 
mon around  some  of  the  islands  in  the  West  Indies. 
At  Guadaloupe  human  bones  have  been  found 
imbedded  in  a  rock  of  this  kind,  whence  were 
obtained  two  imperfect  human  skeletons,  one  pre- 
served at  the  British  Museum,  and  the  other  in  the 
Paris  Museum,  and  from  the  occurrence  of  these 


^BO  ESSAY  ON  LIMESTONES. 

bones,  and  otlier  circumstances,  may  be  inferred  the 
comparatively  modern  origin  of  the  rock  in  question. 
The  Florida  Keys  abound  in  deposits  of  shells  in 
various  states  of  disintegration  and  subsequent  union 
by  cement. 

Among  the  marine  formations  there  are  few  more 
curious  or  interesting  than  coral  reefs  and  islands, 
which  to  a  certain  extent  are  constructed  by  different 
kinds  of  polypiferous  zoophytes  ;  and  they  are  very 
numerous,  mostly  belonging  to  the  genera  Mean- 
drina,  Coryaphillia,  and  Astrea,  particularly  the 
latter.  All  of  them  are  minute  animals,  for  which 
the  coral  tubes  serve  as  habitations.  It  has  been 
supposed  that  the  coral  rocks  descend  in  perpendicu- 
lar columns  to  the  bed  of  the  ocean,  and  cover 
millions  of  acres  of  the  Pacific.  So  great  is  the 
extent,  that  the  inhabitants  of  Disappointment 
Islands  and  those  of  Duff's  Group  pay  visits  to  each 
other  by  passing  over  long  lines  of  reefs  from 
island  to  island,  a  distance  of  six  hundred  miles. 

Many  islands  which  were  visited  by  Capt.  Kotze- 
bue  have  several  groups  of  coral  islands  arranged  in 
a  circular  or  oval  form,  with  openings  among  them 
which  afforded  access  to  the  interior  basin.  These 
islands  seemed  to  be  only  the  upper  portion  of  ridges 
of  unequal  height,  on  the  inside  of  which,  toward  the 
basin  or  lagoon,  where  there  is  still  water,  the 
smaller  and  more  delicate  kinds  of  polypes  carry  on 


ESSAY  ON  LIMESTONES. 


281 


tlieir  operations,  while  the  stronger  species  live  and 
work  on  the  exterior  margin  of  the  bank,  against 
which  a  great  surf  usually  breaks.  These  creatures 
leav^e  off  building  as  soon  as  their  structures  reach 
such  a  heigiit  as  to  be  left  almost  dry  at  the  lowest 
ebb  of  the  tide.  A  mass  of  solid  stone  is  seen,  com- 
posed of  shells  of  molluscs,  and  when  with  them 
broken  off  prickles,  and  fragments  of  coral  cemented 
by  calcareous  matter.  The  ridge  is  raised  by  frag- 
ments of  corals  thrown  up  by  the  waves,  till  it 
becomes  so  high  as  to  be  covered  only  by  high  tides 
at  certain  seasons.  Masses  of  the  stone  thus  formed 
are  sometimes  separated  and  thrown  upon  the  surface 
of  the  reefs,  so  as  gradually  to  augment  its  elevation. 
Tlie  rate  of  growth  of  the  common  branching  Madre- 
pore is  not  over  one  and  a  half  inches  a  year.  Other 
branches  are  open.  This  would  not  be  equivalent  to 
more  than  half  an  inch  in  height  of  solid  coral  for 
the  whole  surface  covered  by  the  Madrepore ;  and  as 
they  are  also  porous,  to  not  cover  over  three-eighths 
of  an  inch  of  solid  limestone.  But  a  coral  plantation 
has  large  bare  patches  without  corals,  and  the  coral 
sands  are  widely  distributed  by  currents,  part  of 
them  to  depths  over  one  hundred  feet,  where  there 
are  no  living  corals.  Not  more  than  one-sixth  of  the 
surface  of  a  reef  region  is  in  fact  covered  with  grow- 
ing species,  which  reduces  the  three-eighths  to  one- 
sixteenth.    Shells   and   other  organic  relics  may 


282 


ESSAY  ON  LIMESTONES. 


contribute  one-quarter  as  much  as  corals.  At  the 
outside  the  average  upward  increase  of  the  whole 
reefground  per  year  would  not  exceed  one-eighth  of 
an  inch,  j^ow  some  reefs  are  at  least  two  thousand 
feet  thick,  which  at  one-eighth  of  an  inch  a  year  cor- 
responds to  190,000  years.  If  the  progressing 
subsidence  essential  to  the  increasing  thickness  were 
slower  than  the  most  rapid  rate  at  which  the  upward 
progress  might  take  place,  the  time  would  be  propor- 
tionally longer.  Coral  formations  are  most  abundant 
in  the  tropical  Pacific,  where  there  are  two  hundred 
and  ninety  coral  islands,  too  numerous  to  mention. 
A  distinction  exists  between  coral  islands  and  coral 
reefs ;  the  first  are  isolated  coral  formations  in  the 
open  sea,  and  the  second  are  banks  of  coral  bordering 
other  lands  or  islands.  It  has  been  already  stated 
that  the  tropics  are  the  hotbed  for  coral  formations  ; 
the  limiting  temperature  of  reef  forming  cdrals  is 
ggo  They  do  not  flourish  where  the  mean  tem- 
perature of  any  month  of  the  year  is  below  that 
degree.  Certain  tropical  coasts  are  exempt  from 
coral  reefs,  for  the  following  reasons :  the  cold  extra- 
tropical  oceanic  currents,  as  in  Western  South 
America ;  muddy  or  alluvial  shores,  or  the  emptying 
of  large  rivers ;  for  coral  polyps  require  clear  sea 
water  and  generally  a  solid  foundation  to  build  upon. 
Also  the  process  of  volcanic  action  destroys  the  life 
of  a  coast ;  also  the  depth  of  water  on  precipitous 


ESSAY  ON  LIMESTONES. 


283 


shores,  for  the  reef  corals  do  not  grow  where  the 
depth  exceeds  one  hundred  feet.  Beyond  that  depth 
til  ere  are  no  growling  corals,  except  some  kinds  that 
enter  but  sparingly  into  the  structure  of  reefs,  the 
largest  of  which  are  the  dendrophylliae. 

The  rock  forming  the  coral  platform  and  other 
parts  of  the  solid  reef,  is  a  white  limestone,  made  out 
of  corals  and  shells:  its  ramification  is  like  that  of 
ordinary  limestones.  In  some  parts  it  contains  the 
corals  imbedded,  but  in  others  it  is  perfectly  com- 
pact, without  a  fossil  of  any  kind,  only  an  occasional 
sliell.  In  no  case  is  it  chalk.  The  compact,  non- 
fossiliferous  kinds  are  found  in  the  lagoons  or  shel- 
tered channels,  the  kind  made  of  broken  corals  on 
the  sea  shore  side,  in  the  face  of  the  waves ;  those 
made  of  corals  standing  as  they  grow  in  sheltered 
waters,  where  the  sea  has  free  access.  The  ])rincipal 
kinds  of  coral  rock  consist  in, 

1.  A  fine  grained,  compact,  and  clinking  lime- 
stone, solid  and  flint-like  in  fracture  as  any  Silurian 
limestone,  and  with  rarely  a  shell  or  fragment  of 
coral.  This  is  a  calcium  variety,  and  wdien  coral  reefs 
and  islands  have  been  elevated,  it  often  makes  up  the 
mass  of  the  rock  exposed  to  view,  it  is  a  puzzle  how 
to  account  for  the  absence  of  the  fossils. 

2.  A  compact  colite  consisting  of  rounded  concre- 
tionary grains,  and  generally  without  any  distinct 
fossils. 


284 


ESSAY  ON  LIMESTONES. 


3.  A  rock  equally  compact  and  hard  with  No.  1, 
but  containing  imbedded  fragments  of  corals  and 
some  shells. 

4.  A  conglomerate  of  broken  corals  and  shells, 
with  little  else,  very  firm  and  solid ;  many  of  the 
corals  several  cubic  feet  in  size. 

5.  A  rock  consisting  of  corals  standing  on  the 
solid  earth,  the  interstices  filled  in  with  coral  sand, 
shells  and  fragments.  In  general,  the  rock  is  exceed- 
ingly solid,  but  in  some  instances  the  interstices  are 
but  loosely  filled. 

All  these  corals,  when  alive  in  w^ater,  are  covered 
throughout  with  expanded  polyps,  emulating  in 
beauty  of  form  and  colors  the  flowers  of  the  land. 
Besides  corals  and  shells,  there  are  also  some  kinds 
of  calcareous  vegetation  called  nullipores,  both 
branching  and  incrusting  in  form,  which  add  to  the 
accumulation.  They  grow  well  over  tlie  edge  of  the 
reof,  in  the  face  of  the  breakers,  and  attain  consider- 
able thickness. 

The  waves  in  their  heavier  movements,  sweeping 
over  the  coral  plantations,  may  be  as  destructive  as 
winds  over  forests.  They  tear  up  the  corals,  and  by 
incessant  perturbation  reduce  the  fragments  to  a 
great  extent  in  to  sand,  and  the  debris  thus  made,  and 
ever  making,  are  scattered  over  the  bottom  or  piled 
upon  the  coast  by  the  tide,  or  swept  over  the  lower 
parts  of  the  reef  into  the  lagoon.    The  corals  keep 


ESSAY  ON  LIMESTONES. 


285 


growing,  and  this  sand  and  the  fragments  go  on 
accumulating,  the  consolidation  of  the  fragmental 
material  makes  the  ordinary  reef  rock.  Thus,  by  the 
help  of  the  waves,  a  solid  reef  structure  is  formed 
from  the  sparsely  growing  corals. 

Where  the  corals  are  protected  from  the  waves, 
they  grow  up  bodily  to  the  surface,  and  make  a  weak 
open  structure  instead  of  the  solid  reef  rock,  or,  if  it 
bo  a  closely  branching  species,  so  as  to  be  firm,  it 
still  wants  the  compactness  of  the^reef  that  has  been 
formed  amid  the  waves.  According  to  their  posi- 
tion, "  there  are  fringing  or  barrier  reefs,  the 
first  are  attaclied  ^directly  to  the  shore,  while  the 
others  are  like  artificial  moles,  separated  from  the 
shore  by  a  channel  of  water.  The  thickness  of  a 
coral  formation  is  very  great,  sometimes  thousands  of 
feet;  the  instances  are  quoted  that  no  bottom  was 
found  at  6,000  fe3t ;  at  the  Fejees,  2  to  3,000  feet. 
Fringe  reefs  form  the  origin  for  the  Atolls,  like  the 
Menchikoff,  as  explained  by  Darwin,  which  are  high 
islands  consisting  of  two  clusters  of  summits,  like 
Mani  and  Oahee  in  the  Ilawaian  group.  It  has  been 
st  ited  that  one  of  the  principal  sources  of  the  lime- 
stone formation  is  formed.  Shells  and  corals,  which 
form  extensive  beds  and  acquire  a  texture  as  firm  as 
any  marble,  and  by  watching  the  process  of  accumu- 
lation, from  the  growth  of  corals  and  the  wear  of  the 
waves,  that  the  remains  of  these  corals  form  a  com- 


286 


ESSAY  ON  LIMESTONES. 


pact  bed  ;  and  we  infer  from  tliis  great  phenomenon 
that  if  we  meet  with  a  limestone  over  this  continent 
containing  remains  of  corals  or  shells,  that  the 
ancient  limestone  was  as  much  a  slowly  formed  rock 
made  of  corals  or  shells  as  the  limestone  of  coral 
seas. 

From  Hirsch's  new  Journal  "  The  Arts "  the 
following  Extract  is  made  with  reference  to  the  reef- 
building  coral. 

The  variety  of  compact  and  branching  corals  far 
exceeds  description :  120  species  are  inhabitants  of 
the  Red  Sea  alone,  and  an  enormous  area  of  the 
Tropical  Pacific  is  everywhere  crowded  with  the 
stupendous  works  of  these  minute  agents,  destined  to 
change  the  present  geological  features  of  the  globe, 
as  their  predecessors  have  done  in  the  remote  ages  of 
its  existence. 

Four  distinctly  different  formations  are  due  to  the 
coral-building  polypes  in  the  Pacific  and  Indian 
Oceans,  namely  :  lagoon  islands  or  atolls,  encircling 
reefs,  barrier  reefs,  and  coral  fringes — all  nearly  con- 
fined to  the  torrid  zone. 

An  atoll  is  a  ring  or  chaplet  of  coral,  enclosing  a 
lagoon  or  portion  of  the  ocean  in  its  centre.  The 
average  breadth  of  that  part  of  the  ring  which  rises 
above  the  surface  of  the  sea  is  about  a  quarter  of  a 
mile,  often  less,  and  it  is  seldom  more  than  from  six 
to  ten  or  twelve  feet  above  the  waves ;  hence  the 


ESSAY  ON  LIMESTONES. 


287 


lagoon  islands  are  not  visible,  even  at  a  very  small 
distance,  unless  covered  by  the  cocoanut,  tbe  palm, 
or  tlie  pandanus,  which  is  frequently  the  case.  On 
the  outside,  the  ring  or  circlet  slopes  down  for  a 
distance  of  one  or  two  hundred  yards  from  its  edge, 
so  that  the  &ea  gradually  deepens  to  about  twenty -live 
fathoms,  beyond  which  the  sides  of  the  ringe  plunge 
at  once  into  the  unfathomable  depths  of  the  ocean, 
with  a  more  rapid  descent  than  the  cone  of  any  vol- 
cano. Even  at  the  small  distance  of  some  hundred 
yards,  no  bottom  has  been  reached  with  a  sounding- 
line  a  mile  and  a  half  long. 

All  the  coral  in  the  exterior  of  the  ring,  to  a 
moderate  depth  below  the  surface  of  the  water,  is 
alive;  all  above  it  is  dead,  being  the  detritus  of  the 
living  part  washed  up  by  the  surf,  which  is  so  heavy 
on  the  windward  side  of  the  tropical  islands  of  the 
Pacific  and  Indian  oceans,  that  it  is  often  heard  miles 
olF,  and  is  frequently  the  first  warning  to  seamen  of 
their  approach  to  an  atoll. 

The  outer  margins  of  Maldave  atolls,  consisting 
chiefly  of  nullipores  and  porites,  are  beaten  by  a  surf 
90  tremendous  that  even  ships  have  been  thrown,  by 
a  single  upheaval  of  the  sea,  high  and  dry  on  the  reef. 
The  waves  give  innate  vigor  to  the  polypes  by  bring- 
ing an  ever-renewed  supply  of  food  to  nourish  them, 
and  oxygen  to  support  life;  besides,  uncommon 
energy  is  given  and  maintained  by  the  heat  of  the 


288 


ESSAY  ON  LIMESTONES. 


tropical  sun,  which  gives  them  power  to  abstract 
enormons  quantities  of  solid  matter  from  the  water 
to  build  their  strong  homes  —  a  power  that  is  efficient 
in  proportion  to  the  energy  of  the  breakers  which 
furnish  the  supply. 

On  the  margin  of  the  atolls,  close  within  the  line, 
where  the  coral  is  washed  by  the  tide,  three  species 
of  nuUipores  flourish  ;  they  are  beautiful  little  plants, 
very  common  in  the  coral  islands.  One  species 
grows  in  thin  spreading  sheets,  like  a  lichen ;  the 
second,  in  strong  knobs  as  thick,  as  a  man's  finger, 
radiating  from  a  common  centre ;  and  the  third 
species,  which  has  the  color  of  peach  blossoms,  is  a 
recticulated  mass  of  stiff  branches,  about  the  thickness 
of  a  crow's  quill.  The  three  species  either  grow 
mixed  or  separately,  and  although  they  can  exist 
above  the  line  of  the  corals,  they  require  to  be  bathed 
the  greater  part  of  each  tide ;  hence  a  layer  two  or 
three  feet  thick,  and  about  twenty  yards  broad, 
formed  by  the  growth  of  the  nullipores,  fringes  the 
circlet  of  the  atolls  and  protects  the  coral  below. 

The  lagoon  in  the  centre  of  these  islands  is  supplied 
with  water  from  the  exterior,  by  openings  in  the  lee- 
side  of  the  ring,  but  as  the  water  has  been  deprived 
of  the  greater  part  of  its  nutritious  particles  and 
inorganic  matter  by  the  corals  on  the  outside,  the 
harder  kinds  are  no  longer  produced,  and  species  of 
more  delicate  forms  take  their  place.    The  depth  of 


ESSAY  ON  LIMESTONES. 


289 


the  lagoon  v^aries  from  fifty  to  seventy  fathom  or  lest^, 
the  bottom  being  partly  detritus,  partly  live  coral. 
In  these  calm,  limpid  waters,  the  corals  are  of  the 
m  )st  varied  and  delicate  structures,  and  the  most 
c'larming  and  dazzling  lines. 

When  the  shades  of  evening  come  on,  the  lagoon 
shines  like  the  milky  way,  with  millions  of  brilliant 
sparks.  The  microscopic  medusa  and  Crustacea,  in- 
visible during  the  day,  form  the  beauty  of  the  night, 
and  the  sea-feather,  vermillion  in  day-light,  now 
waves  with  green  })liosphorescent  light.  This  gor- 
geous character  of  the  sea-bed  is  not  peculiar  to  the 
lagoons  of  the  atolls — it  prevails  in  shallow  water 
throughout  the  whole  coral-bearing  regions. 

We  have  other  materials  of  organic  origin  which 
have  been  formed  into  rocks,  and  which  are  generally 
divided  in  four  groups,  such  as, 

1.  The  calcareous  rocks  from  which  the  limestones 
have  been  formed,  namely,  corals,  shells,  crinoids, 
which  have  a  specific  group  of  '2,428. 

2.  The  silicious,  or  those  which  have  contributed 
to  the  silica  of  rocks,  and  may  have  originated  flints, 
such  as,  the  microscopic  siliceous  shields  of  the 
infusoria  called  diatoms,  which  are  now  regarded 
as  plants;  J,  the  microscopic  siliceous  spicula  of 
sponges. 

3.  The  phosphatic,  or  those  which  have  contributed 
phosphates,  especially   the   phosphate  of  lime,  as 


290 


ESSAY  ON  LIMESTONES. 


bones,  excrements,  and  a  few  shells  related  to  the 
lingula.  Such  excrements  are  called  coprolites,  as 
those  of  birds,  when  in  large  accumulations  guano. 

4.  The  carbonaceous,  or.  those  which  have  afforded 
coal  and  series  of  plants. 

Among  the  calcareous  rocks,  we  have  also  an 
uncrjstalline  limestone  and  a  crystalline, 

1.  The  massive,  which,  as  has  previously  been 
mentioned,  as  being  formed  from  shells  and  corals, 
ground  up  by  the  action  of  the  sea  and  afterwards 
consolidated; 

The  colors  are  dull  gray,  bluish,  brownish  to  black, 
its  composition  is  usually  the  same  as  that  of  calcite, 
carbonate  of  lime,  except  that  impurities,  as  clay  or 
sand,  are  often  present.  They  vary  in  texture,  from 
an  earthy  looking  limestone  to  a  very  compact  semi 
crystalline  one,  and  passes  gradually  into  a  crystalline. 

2.  Magnesian  or  Dolomitic  Limestone,  which  con- 
sists of  carbonate  of  lime  and  magnesia,  but  it  is  not 
distinguishable  in  color  or  texture  from  ordinary 
limestone.    Most  of  our  American  limestones  are, 
magnesian. 

3.  Hydraulic  Limestone.  It  is  an  impure  or  earthy 
limestone,  containing  some  clay,  and  affording  quick- 
lime, and  thence  the  water  cement  is  formed. 

4.  Ooietic  Limestone,  a  rock  consisting  of  minute 
concretionary  spherules,  and  looking  like  the  petri- 
fied row  of  fish. 


ESSAY  ON  LIMESTONES. 


291 


5.  Chalk  is  a  white  earthy  limestone,  which  leaves 
a  trace  on  a  board. 

6.  Marl,  a  clay,  composed  of  a  large  proportion  of 
carbonate  of  lime  ;  and  it  is  called  shell  marl  if  it 
consists  largely  of  shells  or  corals. 

T.  Shell  Limestone  is  a  rock  consisting  entirely  of 
shells  or  corals. 

8.  The  Birdseye  Limestone  is  a  compact  limestone 
which  has  crystalline  points  disseminated  through  it. 

9.  The  Travertin  is  a  massive  but  porous  lime- 
stone formed  by  depositions  from  springs  or  streams^ 
holding  carbonate  of  lime  in  solution,  or  bi-carbon- 
ate.  Such  a  rock  abounds  on  the  river  Avino,  near 
Tivoli,  and  is  used  there  as  building  material. 

10.  Stalagmite,  Stalactite,  depositions  from  water 
trickling  through  the  roofs  of  limestone  caverns, 
from  pendent  calcareous  cones  and  cylinders  from 
the  roofs,  which  are  called  stalactite,  and  incrusta- 
tions on  the  floors  which  are  called  stalagmite  ;  they 
are  usually  translucent.  The  crystalline  limestone 
comprehends  the  granular  limestone,  such  as  the 
statuary  marble,  which  has  a  granular  texture  from 
white  to  gray  color.  The  calcareous  deposits  in  the 
thermal  springs  have  been  mentioned,  and  have  fur- 
nished food  for  speculation  as  to  their  origin  and 
cause  of  their  deposit.  We  find  some  hot  springs  which 
deposit  siliceous  matter,  and  some  calcareous.  The 
Geysers  of  Iceland  contain  siliceous  earths  in  solution 


292 


ESSAY  ON  LIMESTONES. 


aud  deposit  them  on  cooling ;  these  deposits  extend 
over  an  area  of  about  half  a  mile  in  diameter,  and 
from  the  depth  of  a  cleft  near  the  great  Geyser,  the 
siliceous  matter  appears  to  be  more  than  twelve  feet 
in  thickness.  The  hot  springs  of  Furnas,  in  the  vol- 
<3aaic  district  of  St.  Michael,  one  of  the  Azores,  large 
quantities  of  silex,  enveloping  grass,  leaves  and  other 
vegetable  bodies,  some  of  which  are  still  flowering, 
in  the  island  are  seen,  frequently  forming  horizontal 
strata,  siliceous  stalactites  two  inches  long,  and  cov- 
ered with  small  brilliant  quartz  crystals.  The  hot 
springs  of  Arkansas,  in  the  Ozark  Mountains,  form  a 
district  of  extinct  volcanoes  ;  tliey  have  furnished  the 
author  most  exquisite  specimens  of  quartz  crystals  in 
groups  for  his  own  cabinet,  and  excited  the  admira- 
tion of  the  scientific  and  curious  world  when  h? 
exhibited  them  at  the  London  Exhibition  in  1851, 
and  the  variety  of  forms,  as  well  as  the  sizes  and  par- 
ticular appearance,  cannot  be  excelled. 

The  thermal  springs  of  Primarkoon  and  Loor- 
goothe,  in  the  East  Indies,  contain  besides  silica 
various  salts  of  soda. 

The  Travertin  is  by  no  means  confined  to  loca- 
tions where  limestone  districts  are  known,  but  occurs 
indiscriminately  in  all  rock  formations.  In  Au- 
vergne  in  France,  w4iere  the  primary  rocks  are  desti- 
tute of  limestone,  springs  abundantly  charged  with 
carbonate  of  lime  rise  up  through  the  granite  and 


ESSAY  ON  LIMESTONES. 


293 


grass.  In  the  valley  of  the  Elsa,  which  skirts  the 
Appenines  in  Italy,  are  innunerable  springs  which 
have  thrown  down  such  calcareous  precipitates  that 
the  w^hole  ground  in  some  parts  of  Tuscany  is  coated 
with  Travertin,  and  sounds  hollow  under  foot.  A 
most  striking  instance  of  the  rapid  deposit  of  carbon- 
ate of  lime  from  thermal  w^aters  may  be  observed  in 
the  hill  of  San  Yignone,  on  the  high  road  between 
Sienna  and  Home,  a  large  mass  of  Travertin  de- 
scends the  hill,  from  the  point  w^hence  the  spring 
issues  to  the  bank  of  the  Iliver  Orcia,  a  distance  of 
250  feet,  forming  a  mass  of  varying  thickness,  but 
sometimes  200  feet  in  depth,  and  on  the  other  side  of 
the  hill  a  similar  deposit  extends  about  half  a  mile, 
in  parallel  strata,  one  of  which  is  fifteen  feet  thick 
and  constitutes  excellent  building  stone. 

The  hot  springs  of  Wachita,  before  mentioned, 
have  likewise  large  deposits  of  travertin,  forming 
escarpments  along  the  borders  of  the  stream,  into 
which  the  hot  springs  descend. 

.  Among  the  beds  of  the  Potsdam  period,  the  mag- 
nesian  limestone  strata  of  the  Quebec  group  contain 
numerous  fossils,  and  thus  show  that  they  are  marine 
and  that  they  have  the  origin  of  whatever  life  occu- 
pied the  seas.  The  extensive  magnesian  limestones 
of  the  Mississippi  Valley  have  the  same  composition 
and  are  similar  in  compactness  ;  the  natural  inference 
is  that  they  were  also  of  organic  origin.    But  over 


294 


ESSAY  ON  LIMESTONES. 


extensive  regions  they  do  not  contain  a  single  fossil. 
Yet  it  is  to  be  remembered  that  the  sea,  which  grinds 
pebbles  and  sand  and  makes  fine  sandstones,  may 
also  grind  shells  and  make  an  impalpable  limestone. 
This  is  abundantly  exemplified  in  coral  regions,  for 
a  large  part  of  the  limestone  there  made  of  corals  and 
shells  is  as  compact  and  imfossiliferons  as  the  magne- 
sian  limestone  in  question. 

The  only  other  mode  of  origin  is  by  chemical  depo- 
sition. This  could  not  have  taken  place  in  the  open 
seas,  for,  owing  to  the  oceanic  currents,  the  waters 
have  a  remarkable  uniformity  of  composition,  and  no 
local  deposition  can  take  place.  It  requires,  there- 
fore, an  elevation  above  the  sea  and  the  existence  of 
calcareous  mineral  springs,  and  springs  on  a  wonder- 
fully vast  scale,  for  a  formation  as  extensive  as  the 
magnesian  limestone  of  the  Potsdam  period.  Such 
a  condition  of  things  is  improbable.  Moreover,  the 
depositions  would  have  a  structure  wholly  unlike 
that  of  the  magnesian  limestone.  Whoever  has  seen 
the  travertin  beds  of  Tivoli,  which  are  the  largest  of 
the  chemical  calcareous  deposits  formed  in  the  present 
era,  will  appreciate  the  wide  distinction  between  the 
mass  made  up  of  a  series  of  incrustations,  curving 
with  all  sorts  of  fantastic  irregularities,  and  the  dense 
even-grained  limestone  of  the  calciferous  epoch.  The 
oolitic  structure  of  part  of  this  limestone  has  a  paral- 
lel in  the  oolitic  coral  rock  of  Key  West,  which  is 
also  without  imbedded  corals  or  shells. 


ESSAY  ON  LIMESTONES. 


295 


It  is  curious  to  reflect  that  if  the  bottom  of  the 
equatorial  seas,  wliere  atolls  abound,  were  upraised 
aud  laid  dry,  we  should  behold  mountain  peaks 
arid  ridges  composed  fundamentally  of  volcanic,  gra- 
nitic and  other  rocks,  on  which  tabular  masses  of 
limestone  would  repose.  Some  of  these  calcareous 
cappings  would  be  continuous  over  an  area  three 
miles,  others  above  300  miles  in  circumference,  while 
their  thickness  might  vary  from  1,000  to  10,000  feet 
or  more.  They  would  consist  principally  of  corals 
and  shells — in  some  places  entire,  in  others  broken. 
In  the  lower  regions  of  the  same  continent,  and  be- 
tween the  high  table  lands  or  mountain  ridges,  there 
would  often  be  no  contemporary  deposits,  or  where 
exceptions  occurred  to  this  rule  the  calcareous  strata 
would  differ  in  their  nature  as  much  as  in  the  species 
of  fossils  which  they  enclosed  from  the  tabular  masses 
of  coral.  It  has  been  observed  that  the  softer  corals^ 
when  they  decompose  in  the  lagoon,  are  resolved  into 
a  white  mud,  which,  when  dry,  is  undistinguishable 
from  common  chalk'  and  inference  may  be  drawn 
that  a  recent  cretacrous  formation  may  now  be  in 
progress  in  many  parts  of  the  Pacific  and  Indian 
oceans. 

It  is,  however,  more  than  probable  that  lime^ 
which  is  generally  contained  in  sea  water  and 
secreted  so  plentifully  by  the  testacea  and  corals  of 
the  Pacific,  may  have  been  derived  either  from  springs 


-296 


ESSAY  ON  LIMESTONES. 


rising  up  in  tlie  bed  of  the  ocean,  or  from  rivers  fed 
by  calcareous  springs,  or  impregnated  with  lime  de- 
rived from  disintegrated  rocks,  both  volcanic  and 
hypogene ;  and  if  this  be  admitted,  the  greater  pro- 
portion of  limestone  in  the  more  modern  formations, 
as  compared  to  the  most  ancient,  will  be  explained, 
for  springs  in  general  hold  no  argillaceous,  and  but  a 
small  quantity  of  siliceous  matter  in  solution,  but 
they  are  continually  substracting  calcareous  matter 
from  the  inferior  rocks.  The  constant  transfer, 
therefore,  of  carbonate  of  lime  from  the  lower  or  older 
portions  of  the  earth's  crust  to  the  surface,  must  cause 
^it  all  periods,  and  throughout  an  indefinite  succession 
of  geological  epochs,  a  preponderance  of  calcareous 
matters  in  the  newer,  as  contrasted  with  the  older, 
formations. 

The  chalk  of  which  allusion  has  just  been  made, 
baving  their  origin  likewise  in  the  lagoons  where  the 
corals  have  been  converted  into  mud,  belongs  to  the 
tertiary  strata  called  the  cretaceous  or  chalky  group 
and  is  but  a  limestone  or  carbonate  of  lime.  Al- 
though usually  soft,  this  substance  passes  in  many 
localities  by  a  gradual  change  into  a  solid  stone  used 
for  building,  the  stratification  is  often  obscure,  except 
where  rendered  distinctly  alternating  layers  of  flint. 
These  layers  are  from  2  to  4  feet  di extant  from  each 
other  and  from  3  to  6  inches  in  thickness,  occasionally 
in  continuous  beds,  but  more  frequently  in  nodules. 


ESSAY  ON  LIMESTONES. 


29r 


No  doubt  exists  but  what  the  chalk  was  formed  in  an 
open  sea  of  some  depth,  but  how  so  large  a  quantity 
of  this  peculiar  white  substance  could  have  accumulat- 
ed over  an  erea  many  hundred  miles  in  diameter  and 
some  of  the  extreme  points  of  which  are  distant  more 
than  1000  geographical  miles  from  each  other,  is  of 
the  greatest  interest  and  its  derivation  from  the  decay 
of  corals  and  shells  has  given  rise  to  many  philo- 
sophical investigations.  The  most  difficult  problem 
is  the  origin  of  the  flint  in  the  chalk,  whether  it  occurs 
in  isolated  nodules  or  continuous  layers.  It  seems 
that  there  was  originally  siliceous  as  well  as  cal- 
careous earth  in  the  muddy  bottom  of  the  cretaceous 
sea,  at  least  when  the  upper  chalk  was  deposited. 
Whether  both  these  earths  could  have  been  alike 
supplied  by  the  decay  of  organic  bodies,  may  be  a 
matter  of  speculation.  The  flints  which  is  contained 
as  nodules  in  the  chalk  are  distributed  in  layers 
through  it  like  the  hornstone  in  the  earlier  limestones; 
they  are  more  or  less  rounded  and  often  assume  fan- 
tastic shapes;  sometimes  they  resemble  rolled  stones, 
but  in  fact  all  are  of  concretionary  origin.  The 
exterior  of  the  nodules  for  a  little  depth  is  frequently 
white  and  penetrated  by  chalk,  proving  that  they 
are  not  introduced  boulders  or  stone  but  have  origi- 
nated where  they  now  lie,  and  we  attribute  the  parallel 
disposition  of  the  flints  layers  to  successive  deposition. 
The  distances  between  the  layers  must  have  been 


298 


ESSAY  ON  LIMESTONES. 


regulated  by  tlie  intervals  of  precipitation,  each  new 
mass  forming  at  the  bottom  of  the  ocean  a  bed  of 
pulpy  fluid,  which  did  not  penetrate  the  preceeding 
bed  on  which  it  rested,  because  the  consolidation  of 
the  last  has  so  far  advanced  as  to  prevent  snch  inter- 
mixture; it  remains,  therefore,  a  singular  phenome- 
non not  yet  satisfactorily  accounted  for.  Perhaps,  as 
the  specific  gravity  of  the  siliceous  exceeds  that  of 
the  calcareous  particles,  the  heavier  flint  may  have 
sunk  to  the  bottom  of  each  stratum  of  soft  mud. 
How  far  and  wide  this  mud  has  been  scattered  by 
oceanic  currents  may  be  seen  by  the  area  over  which 
the  white  chalk  preserves  a  homogenous  aspect,  that 
we  can  hardly  find  an  analogous  deposit  of  recent 
date  ;  chalk  is  found  from  the  north  of  Ireland  to  the 
Crimea,  a  distance  of  1,140  geographical  miles,  and 
from  the  south  of  Sweden  to  Bordeaux,  about  840 
geographical  miles.  The  chalk  cliffs  of  the  English 
Channel  form  one  great  continuous  mass  on  both 
sides,  in  the  neighborhood  of  London  and  Paris 
basin. 

Chalk  forms  one  of  the  rocks  of  the  cretacious 
period.  It  is  not  found  in  America,  but  the  creta- 
cious limestone  of  this  formation  comprises  very 
extensive  beds,  and  is  divided  into  two  great  epochs 
— 1,  that  of  the  earlier  cretaceous,  and  2,  the  epoch 
of  the  later  cretaceous ;  they  extend  from  New  Jersey 
to  South  Carolina,  along  the  Gulf  borders,  and 


ESSAY  ON  LIMESTONES. 


299 


through  a  large  part  of  the  Western  Interior  region, 
over  the  slopes  of  the  Rocky  Mountains,  from  Texas 
northward  and  far  into  the  Colorado  region,  on  the 
west  of  British  America  and  Arctic  Sea,  but  they  are 
unknown  on  the  Atlantic  borders  north  of  New  York. 
The  rocks  comprise  beds  of  sand,  marl,  clay,  loosely 
aggregated  shell  limestone,  and  compact  limestone, 
and  the  sandy  layers  are  predominating,  and  are  of  va- 
rious colors  ;  white,  gray,  reddish  and  dark  green,  and 
though  sometimes  solid,  they  are  often  so  loose  that 
they  may  be  rubbed  to  pieces  in  the  hand,  or  worked 
out  by  a  pick  and  sliovel.  Layers  of  potters'  clay 
occur  in  the  series. 

The  marl  of  New  Jersey  and  elsewliere,  which  is  a 
dark  green  sandy  variety  and  forms  very  extensive 
beds,  is  called  Greensand  ;  is  a  green  silicate  of  iron 
and  potash,  with  a  trace  of  phosphate  of  lime,  and 
this  makes  it  highly  valuable  for  fertilizing  purposes. 
The  cretaceous  formation  has  a  thickness  in  New 
Jersey  of  400  to  500  feet ;  in  Alabama,  500  to  600 
feet ;  in  Texas,  about  800  feet ;  and  in  the  region  of 
the  upper  Missouri,  2,000  to  2,500  feet. 

The  upper  or  later  cretaceous  period,  comprises  the 
beds  on  the  Atlantic  and  Gulf  borders  and  in  New 
Jersey,  while  the  lower  are  re})resented  in  the  West- 
ern Interior  region,  including  Texas. 

The  cretaceous  beds  of  Europe  have  been  divided 
into : 


300 


ESSAY  ON  LIMESTONES. 


1.  The  lower  cretaceous,  including — England, 
the  lower  greensand,  800  to  900  feet  thick,  and  in 
other  regions  beds  of  clay  and  limestone,  sometimes 
chalky. 

2.  Tlie  middle  cretaceous,  including  in  Eng- 
land— the  clayey  beds  or  marls  called  gault,  150 
feet  thick ;  and  J,  the  upper  greensand,  100  feet 
thick. 

3.  The  upper  cretaceous,  including  in  England  the 
beds  of  chalk,  in  all  about  1,200  feet.  It  consists  of 
— the  lower  or  gray  chalk  or  chalk  marl  without 
flint ;  J,  the  white  chalk  containing  flint ;  <?,  the 
Maestricht  beds,  rough  friable  limestone  at  Maes- 
tricht,  Denmark,  100  feet  thick. 

The  life  of  the  cretaceous  period  in  Europe  resem- 
bled that  of  America,  but  was  far  more  abundant. 
Nearly  6,000  species  of  animals  have  been  described, 
more  than  half  of  them  molluscs  ;  whereas,  in  Amer- 
ica the  whole  number  does  not  exceed  2,000. 

The  great  Interior  Continental  basin,  which  had 
been  a  limestone-making  region,  for  the  most  part, 
from  the  earliest  period  of  the  Siluvian,  was  still  in 
its  southern  part,  as  in  Texas,  continuing  the  same 
work,  for  limestones  80  feet  thick  were  there  formed. 
To  the  north  of  Texas,  where  the  waters  were  shal- 
lower, there  appears  to  have  been  none  of  the  echino- 
derms,  corals,  orbitolinae,  &c.,  which  were  common 
in  Texas. 


ESSAY  ON  LIMESTONES. 


301 


Having  stated  of  the  extent  of  the  cretaceous  or 
chalk  formation  as  of  a  recent  origin  or  mesozoic 
time,  we  find  before  our  doors  the  limestones  in  large 
deposits  on  the  verge  of  the  azoic  time. 

New  York  Island,  which  is  about  13  miles  long, 
consists  of  eight  different  formations  of  nietamorphic 
rocks,  (a  term  first  proposed  by  Lvell,  of  the  altered 
strata  of  the  sedimentary  rocks,)  among  which  the 
limestone  represents  a  very  conspicuous  part ;  they 
are,  according  to  Cozzens,  as  follows : 

1.  Granite,  beginning  at  28tli  Street,  a  little  east 
of  8th  Avenue;  running  to  ^^orth  Kiver  at  32d 
Street,  up  to  60th  Street ;  crops  out  at  80th  Street^ 
near  the  Croton  Water  Works  Receiving  Reservoir. 

2.  Syenite  crops  out  at  the  north  edge  of  the  Ser- 
pentine, probably  but  a  boulder  of  greenstone. 

3.  Serpentine. — Between  54th  and  62d  Streets,  the 
shore  and  10th  Avenue,  four  or  more  small  knolls  of 
black  serpentine  are  visible,  with  scales  of  silvery 
and  golden  talc,  accompanied  by  a  vein  about  12 
feet  wide,  of  anthophyllite.  This  vein  is  in  a  vertical 
position,  and  actinolite  is  found  embedded  in  the  ser- 
pentine. At  the  south  end  there  is  a  vein  of  carbon- 
ate of  lime,  resembling  much  a  verde  antique,  on 
account  of  containing  small  specks  of  serpentine  dif- 
fused through  it. 

4.  Gneiss. — This  rock  is  more  abundant  on  the 
Island  than  any  other ;  beginning  at  the  Battery, 

13 


302 


ESSAY  ON  LIMESTONES. 


which  it  underlies,  may  be  seen  at  East  14th  Street, 
and  18  feet  below  the  surface  in  8th  Street.  It  un- 
derlies Governor's  Island  at  its  most  southern  extent, 
passing  through  New  York  Island,  and  running 
through  the  greater  part  of  Westchester  County ; 
forms  the  rock  at  the  straits  called  Hell-Gate,  and 
then  underlying  Long  Island.  The  gneiss  of  New 
York  Island  is  a  peculiar  variety;  has  more  mica 
than  common. 

5.  Hornblende  Slate. — This  rock  is  associated  with 
the  gneiss  in  many  parts  of  the  Island — at  Spuyten 
Devil  bluff,  at  the  north  end  of  the  Island,  and  at 
Manhattanville. 

6.  Quartz  Kock. — On  the  10th  Avenue,  near  60th 
Street,  veins  of  quartz  of  various  thicknesses,  gray 
and  granular. 

7.  Primitive  (so-called)  Limestone,  of  Kingsbridge, 
is  a  dolomite,  and  has  all  the  varieties  of  white,  gray 
and  light  blue,  granular  and  coarse  marble.  It  be- 
gins at  the  south  end  ot  Dykeman  Farm,  and  runs 
through  the  middle  of  the  Island  to  Spuyten  Devil 
Creek ;  the  formation  rests  on  granite. 

8.  Diluvium. -^This  formation  covers  almost  all 
the  Island ;  it  is  100  feet  in  depth  on  the  lower  end 
of  the  Island  ;  there  are  found  types  of  all  the  rocks 
of  the  valley  of  the  Hudson. 

Dr.  R.  P.  Stevens  states  that  no  where  on  the  face 
of  the  globe  could  such  numerous  sections  of  meta- 


ESSAY  ON  LIMESTONES. 


303 


morpliic  rocks  be  seen  in  so  easy  and  accessible  a 
manner  as  on  the  npper  end  of  our  Island.  We  find 
gneiss  forming  the  main  mass  of  the  Island ;  then 
comes  the  granite,  hornblende,  anthophyllite  and 
other  masses.  The  limestone  is  found  independent 
of  the  large  deposit  at  Kingsbridge,  at  132d  Street, 
east  of  6th  Avenue,  reposing  conformably  upon  gneiss, 
which  is  a  continuation  southward  of  the  limestone 
of  Westchester  County,  Between  4th  and  3d  Ave- 
nues, East  123d  Street,  another  bed  of  limestone,  al- 
ways the  gneiss  either  on  the  eastern  and  western 
flanks.  In  the  excavation  of  a  culvert  in  East  60th 
Street,  between  3d  and  4th  Avenues,  the  axis  of 
limestone,  18  feet  beneath  the  street,  was  visible. 
This  fold  of  limestone  has  been  cut  through  at  the 
Montauk  Steel  Works,  on  the  mainland  at  Mott 
Haven,  where  its  base  is  100  feet  wide  and  20  feet 
high,  and  large  masses  of  limestone  were  seen  thrust 
into  the  solid  gneiss.  At  Melrose,  another  bed  of 
limestone,  traceable  to  the  Harlem  River,  as  well  as 
at  Hastings ;  the  large  bed  underlies  the  Harlem 
River,  continuing  southwards. 

Dr.  Stevens  has  good  geological  reasons  for  infer- 
ring that  the  N"orth  River  flows  through  fractures 
and  abrasions  of  folds  of  gneiss  and  limestone,  from 
Haverstraw  Bay  to  the  Narrows. 

Limestones  increase  with  extreme  slowless;  from 
five  to  ten  feet  of  fragmental  deposits  will  accumulate 


304 


ESSAY  ON  LIMESTONES. 


while  one  of  liiriestone  is  forming.  This  conclusion 
is  sustained  by  the  ratio  in  any  given  period  between 
the  fragmental  rocks  of  the  Apalacliians  and  the 
limestones  of  the  interior  basin.  It  may  well  be  here 
noticed  that  the  different  kinds  of  rocks  have  been 
conveniently  divided  into  fragmental  and  crystalline 
rocks.  The  first  are  made  up  of  pebbles,  sand  or 
clay,  either  deposited  as  the  sediment  of  moving  wa- 
ters as  formed  and  accumulated  through  other 
means — as  ordinary  conglomerated  sandstones,  clay 
rocks,  tufas  and  some  limestones.  -The  larger  part  of 
the  rocks  here  included  are  made  of  sedimentary 
material,  and  are  commonly  called  sedimentary 
rocks.  They  are  stratified  rocks,  that  is,  consist  of 
layers  spread  out  one  over  another.  Many  of  them 
are  fossiliferous  rocks,  or  contain  fossils.  The 
crystalline  rocks  have  a  crystalline  instead  of  a 
fragmentary  character.  The  grains,  when  large 
enough  to  be  visible,  are  crystalline  grains,  and  not 
water  worn  particles  or  fragments  of  other  rocks, 
such  as  granite,  micaschist,  basalt.  Tlie}^  may  have 
been  crystallized  either  from  fusion  like  lava  or 
basalt,  when  they  are  called  igneous  rocks,  or  from 
solution  or  with  some  limestones,  or  through  long-con- 
continued  heat  without  fusion.  By  this  method 
sedimentary  beds  have  been  altered  into  granite, 
gneiss,  micaschist,  and  compact  limetone  into  statu- 
ary marble.    When  a  bed  originally  sedimentary  has 


ESSAY  ON  LIMESTONES. 


305 


been  metamorphosed  into  a  crystalline  one,  rocks  of 
tliis  kind  are  called,  metamorphic  rocks.  The  former 
division  of  the  rocks  in  aqueous,  volcanic,  plutonic 
and  metamorphic  was  made  in  the  infancy  of  science, 
when  all  formations,  whether  stratified  or  unstrati- 
fied,  earthy  or  crystalline,  with  or  without  fossils, 
were  alike  regarded  as  of  aqueous  origin. 

A  separate  subdivision  is  made  of  the  calcareous 
rocks  or  limestone,  which  are  mostly  sedimentary  in 
original  accumulation,  but  generally  lose  that  appear- 
ance as  they  solidify.  The  rock  masses  of  the  globe, 
occur  under  three  conditions  :  1st,  the  stratitied  ;  2d, 
the  unstratified  ;  and  3d,  the  vein  condition.  The  first 
may  be  considered  in  the — 1,  the  nature  of  stratifica- 
tion ;  2,  the  structure  of  layers  ;  3,  the  positions  of 
strata,  their  natui'al  positions  and  dislocations  ;  4th, 
the  general  arrangement  of  strata  or  their  chronologi- 
cal order. 

By  chronological  order  is  understood  the  arrange- 
ment of  the  rocks  of  the  difiterent  continents  in  a 
chronological  series. 

We  found  that  North  America  has  some  large 
blanks  in  the  series,  which  in  Europe  are  full ;  and 
in  this  way  various  countries  are  contributing  to  its 
perfection.  The  series  has  been  divided  in  ages, 
based  on  the  progress  of  life  : 

I.,  The  Azoic  age,  containing  no  traces  of  animal 
life. 


306 


ESSAY  ON  LIMESTONES. 


II.  ,  The  Silurian  age,  or  age  of  mollusks,  the 
mollusks  being  the  dominant  race. 

III.  ,  The  Devonian  age,  or  age  of  fishes,  where 
fishes  form  the  dominant  race. 

lY.,  The  Carboniferous  age,  or  age  of  aerogens^ 
characterized  by  coal  Y^lants  or  aerogens. 

Y.,  The  Reptilian  age,  reptiles  the  dominant  race. 

YI.,  The  Mammalian  age,  mammals  the  dominant 
race. 

YII.,  The  age  of  man. 

In  order  to  explain  these  divisions  more  fully,  we 
will  state  of  the  thickness  of  the  stratified  rocks. 
The  whole  thickness  of  the  rocks  in  the  series  is 
fifteen  or  sixteen  miles ;  but  this  includes  the  sum  of 
the  whole  grouped  in  one  pile.  As  the  series  is 
nowhere  complete,  this  cannot  be  the  thickness 
observed  in  any  one  region.  The  rocks  of  'New  York 
down  to  the  azoic,  counting  all  as  one  series,  are 
about  13,000  feet  in  thickness.  They  include  only 
the  Silurian  and  Devonian  (excepting  the  triassic  in 
the  southeast).  To  the  north  they  tliin  out  to  a  few 
feet,  while  they  thicken  southward  towards  Pensyl- 
vania.  The  rocks  in  Pennsylvania  include  the  car- 
boniferous, and  the  whole  thickness  is  at  least  40,000 
feet.  In  Yirginia  the  thickness  is  still  greater,  but  no 
exact  estimate  has  been  made.  In  Indiana  and  the 
other  States  west  it  is  only  4,000,  although  extending 
to  the  top  of  the  carboniferous.    The  greater  part  of 


ESSAY  ON  LIMESTONES. 


307 


the  continent  of  North  America,  east  of  the  Missis- 
sippi, is  destitute  of  rocks  above  the  carboniferous. 

In  Europe  the  rocks  of  the  later  periods  are  far 
more  complete  than  in  North  America,  while  the 
older  also,  according  to  the  estimates  stated,  exceed 
the  American. 

In  Great  Britain  the  thickness  to  the  top  of  the 
carboniferous  is  over  60,000  feet,  and  from  the  carbo- 
niferous to  the  top  of  this  series  little  less  than  10,000 
feet  more.  This  amount  is  the  sum  of  the  thickest 
deposits  of  the  several  formations  and  not  the  thick- 
ness observed  in  any  particular  place. 

The  ages  above  referred  to  belonging  to  rocks  such 
as  the  age  of  mollusks  or  silurian  and  the  age  of 
fishes,  &c.,  we  have  another  signification  in  them, 
subdivision  of  geological  time,  such  as  : 

I.  ,  Azoic  time  or  age,  meaning  absence  of  life. 

II.  ,  Polseozoic  time,  or  ancient  life — 

1.  The  age  of  mollusks,  or  Silurian, 

2.  "     "    "  fishes,  or  Devonian, 

3.  "     "    "  coal  plants,  or  carboniferous. 

III.  ,  Mesozoic  time,  or  mediaeval  age, 

4.  The  age  of  reptiles, 
ly.,  Cenozoic  time,  or  recent  life, 

5.  The  age  of  mammals. 
Y.,  Era  of  mind, 

6.  The  age  of  Man. 


308 


ESSAY  ON  LIMESTONES. 


We  have  also  the  subdivisions  into  periods,  epochs, 
and,  according  to  Lyell,  also  the  Eocene,  Miocene 
and  Pliocene  subdivisions  of  the  age  belonging  to  the 
Tertiary  period. 

How  long  or  how  far  apart  time  was  required  of 
the  creation  and  extinction  of  these  periods  we  have 
no  definite  data  to  show  ;  but  all  the  facts  of  geology 
tend  to  dictate  an  antiquity  of  which  we  are  begin- 
ning to  form  but  a  dim  idea.  Take  for  instance  one 
single  formation,  the  chalk  of  the  English  coast, 
which  consists  entirely  of  shells  and  fragments  of 
shells  deposited  at  the  bottom  of  an  ancient  sea,  far 
away  from  any  continent,  and  take  the  rate  of  depo- 
sition at  10  inches'  in  a  century ;  the  chalk  is 
more  than  1,000  feet  in  thickness,  and  would  have 
required  therefore  more  than  1 '20,000  years  for  its 
formation.  The  fossiliferous  beds  of  Great  Brittain, 
as  a  whole,  are  more  than  7,000  feet  in  thickness,  and 
many  which  within  the  United  States  measure  only 
a  few  inches,  on  the  continent  expand  into  strata  of 
immense  depth,  while  others  of  great  importance 
elsewhere  are  wholly  wanting  with  us  (many  epochs 
in  the  Jurassic  period) ;  for  it  is  evident,  that  during 
all  the  different  periods  in  which  Great  Brittain  has 
been  dry  land,  strata  have  been  forming  elsewhere, 
not  with  us.  Many  strata  now  existing  have  been 
formed  at  the  expense  of  older  ones ;  thus  all  the 
flint  gravels  in  the  southeast  ot  England  have  been 


ESSAY  ON  LIMESTONES. 


309 


produced  by  the  destruction  of  chalk.  This  again  is 
a  very  slow  process.  A  cliff  500  feet  high  will  be 
Avorn  away  at  the  rate  of  an  inch  in  a  century.  When 
a  fall  of  cliff  has  taken  place  the  fragments  serve  as 
a  protection  to  the  coast,  until  they  have  been  gradu- 
ally removed  by  the  w^ave.  The  Wealden  Yalley  is 
twenty-two  miles  in  breadth ;  on  these  data  it  has 
been  calculated,  that  the  denudation  of  the  Weald 
must  have  required  more  than  150,000,000  of  years. 

But  preceding  the  appearance  of  animal  life,  we 
only  know  that  our  globe  was  at  one  time  in  a  state 
of  universal  fusion,  and  that  the  crystaline  rocks 
underwent  a  process  in  which  sand,  clay,  and  lime- 
stone were  deposited,  and  these  materials  formed  the 
original  crust. 

The  Origin  of  the  Alkalies  Contained  in  Sohible 
Glass. 

The  two  alkalies  employed  in  the  manufacture  of 
silicate  are  potash  and  soda,  the  oxides  of  the  metals 
potassium  and  sodium ;  both  of  which  were  discover- 
ed in  1807  by  Sir  Humphrey  Davy.  They  were 
decomposed  by  him  by  means  of  a  powerful  galvanic 
current.  Before  that  time  all  alkalies  and  alkaline 
earths  were  supposed  to  be  elementary  bodies.  The 
metals  liave  since  been  prepared  by  heating  in  an 
iron  retort  either  the  potash  or  soda,  with  charcoal, 


310 


ORIGIN  OF  THE  ALKALIES 


at  a  high  temperature.  By  this  process,  the  carbon, 
at  the  high  temperature,  is  able  to  take  the  oxygen 
from  the  potash  or  soda,  forming  a  carbon  monoxide, 
which  escapes  as  a  gas,  while  the  metal,  either  potas- 
sium or  sodium,  being  volatile  at  a  red  heat,  distilk 
over.  The  preparation  of  these  metals  is  attended 
with  many  difficulties,  and  requires  special  precau- 
tions, as  the  vapors  of  these  metals  not  only  take  fire 
when  brought  in  contact  with  the  air,  but  decompose 
water,  combining  with  the  oxygen,  and  liberating 
hydrogen ;  hence  tlie  metallic  vapors  must  be  cooled 
with  naptha  or  petroleum,  which  do  not  contain  any 
oxygen.  It  is  indispensably  necessary  to  distill  the 
metals  a  second  time  for  purifying  them  and  freeing 
them  from  a  black  explosive  compound,  which  invari- 
ably forms  in  the  original  preparation  and  has  caused 
several  fatal  accidents. 

Potassium. — Is  a  bright,  silver  white  metal,  which 
can  easily  be  cut  with  a  knife  at  the  ordinary  tempera- 
ture, is  brittle  at  0^,  melts  at  62^.5  Fahrenheit,  and 
does  not  become  pasty  before  melting.  When  heated 
to  a  temperature  somewhat  below  red  heat,  potassium 
sublimes,  yielding  a  fine,  green-colored  vapor.  This 
metal  rapidly  absorbs  oxygen,  when  exposed  to  the 
air,  and  becomes  converted  into  a  white  oxide. 
Thrown  into  water,  one  atom  of  potassium  displaces 
one  of  hydrogen  from  the  water,  forming  potassium 
hydroxide,  or  potash.    This  takes  place  with  such 


CONTAINED  IN  SOLUBLE  GLASS, 


311 


force,  that  the  heat  developed  is  sufficient  to  ignite 
the  hydrogen  thus  set  free,  and  the  flame  becomes 
tinged  with  the  peculiar  purple  that  is  characteristic 
of  the  potassa  compounds,  whilst  the  water  attains 
an  alkaline  reation  from  the  potash  which  is  formed. 
Potassium  also  combines  directly  with  chlorine,  sul- 
phur, and  many  other  non-metals^  evolving  heat  and 
light. 

The  original  source  of  potassium  compounds  is  the 
felspar  of  the  granite  rocks,  containing  from  ten  to 
twelve  per  cent.,  and  mica,  containing  from  live  to 
six  per  cent,  of  potash.  Up  to  the  present  time  this 
source  has  not  been  used  for  the  manufacture  of  the 
potassium  salts,  for  the  reason  that  no  cheap  and 
easy  mode  has  yet  made  available  for  separating  the 
potash  from  the  silicic  acid,  with  which  it  is  com- 
bined in  felspar  and  mica.  The  grand  natural  source 
from  which  the  supply  of  potash  is  obtained  is  the 
ashes  of  wood  and  other  vegetable  matter.  The 
potassium  exists  in  tha  plants  previous  to  combustion, 
having  been  absorbed  by  them  from  the  soils  in 
which  they  grow ;  the  soils  obtain  the  potash  from 
the  decomposition  of  rocks,  clay,  etc.  It  is  also 
found,  combined  with  other  substances,  in  sea  water. 
Potash  is  now  generally  obtained  from  the  ashes  of 
plants,  from  which  it  is  leached  out,  or  by  filtering 
water  through  them  and  boiling  down  the  clear 
liquid,  which,  on  evaporation,  produces  the  crude 


312 


ORIGIN  OF  THE  ALKALIES 


potash,  whicli  is  then  purified.  It  used  to  be  manu- 
factured to  a  great  extent  in  the  States  of  'New  York, 
Ohio  and  Michigan,  and  was  called  pearl  ash,  and 
when  perfectly  refined,  pearl  or  pot  tartar.  Some  of 
the  other  potassium  salts,  such  as  the  nitrate  and 
chloride,  are  found  in  large  quantities  in  various 
localities  as  deposits  on  the  surface,  or  in  the  interior 
of  the  earth.  The  sources  of  nitrate  of  potash,  or 
saltpetre,  have  been  sufficiently  well  known.  The 
chloride  of  potassium  occurs  in  beds,  together  with 
rock  salt,  in  Stassfurth,  near  Halle,  in  Prussia,  in 
considerable  quantities,  and  is  largely  employed  by 
gunpowder  manufacturers  for  the  conversion  of  nit- 
rate of  soda  into  that  of  potash.  There  have  been 
already  described  thirteen  varieties,  all  containing 
the  chloride  with  the  salt.  The  utilization  of  sea 
water  for  the  extraction  of  potash  salts  is  about  to  be 
tried  in  Europe  on  a  large  scale.  All  potassium  salts 
are  soluble  in  water,  and  impart  a  violet  color  to 
flame.  The  spectrum  of  this  flame  is  distinguished 
by  two  bright  lines,  one  red,  and  one  violet. 

Sodium. — This  metal  resembles  in  external  appear- 
ance the  metal  potassium.  It  is,  however,  procured 
more  easily  than  the  latter,  by  reducing  the  carbon- 
ate of  soda  in  the  presence  of  carbon.  It  is  now 
manufactured  in  large  quantities  for  the  preparation 
of  other  metals,  especially  magnesium  and  aluminum, 
as  potassium  was  formerly  used  for  the  same  purpose. 


CONTAINED  IN  SOLUBLE  GLASS. 


313 


The  metal  distills  over,  and  is  condensed  in  petro- 
leum. It  is  a  silver-white  metal,  soft  at  ordinary 
temperature,  melting  at  95.6^  and  volatilizing  below 
a  red  heat.  When  thrown  upon  water  it  floats  and 
rapidly  decomposes  the  same  with  disengagement  of 
hydrogen,  soda  being  formed.  If  the  water  be  hot, 
or  be  thickened  with  starch,  the  globule  of  the  metal 
becomes  so  much  heated  as  to  enable  the  hydrogen 
to  take  Are. 

The  Compounds  of  Sodium  are  very  widely  diflused, 
being  contained  in  enormous  quantities  in  the  primi- 
tive granitic  rocks.  They  are  readily  obtained  from 
sea-water,  which  contains  nearly  three  per  cent,  of 
chloride  of  sodium  or  the  common  salt  of  the  kitchen. 
There  are  large  deposits  of  salt  in  Galicia,  Prussia, 
England,  and  this  country,  (as  is  the  case  in  Louis- 
iana and  Nevada  and  on  the  island  of  San  Domingo) 
and  it  was  formerly  obtained  from  the  ashes  of  sea 
plants,  or  kelp,  in  the  same  manner  as  potash  was 
})repared  from  land  plants.  At  present,  however, 
the  carbonate  of  soda  is  manufactured  on  an  enor- 
mously large  scale  from  the  sea-salt,  especially  in 
England,  and  is  known  in  commerce  as  soda-ash, 
which  is  indispensable  in  glass-making,  soap-manu- 
facture, bleaching,  and  for  various  other  purposes  in 
the  arts.  No  less  than  two  hundred  thousand  tons 
of  salt  are  annually  consumed  in  the  alkali  works  of 
Great  Britain. 


314 


ORIGIN  OF  THE  ALKALIES. 


Soda-ash  is  prepared  from  sea-salt  by  a  series  of 
chemical  operations,  such  as  that  of  the  production 
of  the  sulphate  or  salt-cake,  and  the  reduction  of  that 
to  soda-ash.  The  first  is  obtained  by  heating  oil  of 
vitriol  with  common  salt,  in  a  reverberatory  furnace, 
whereby  the  sodium  is  separated  from  the  chlorine 
with  which  it  is  combined,  and  uites  with  oxygen 
and  sulphuric  acid  to  form  sulphate  of  soda,  or  anhy- 
drous glauber  salt.  The  liberated  chlorine  combines 
with  the  hydrogen  of  the  water  contained  in  the  sul- 
phuric acid,  to  form  hydrochloric  acid,  which  is 
collected  as  a  commercial  article.  The  sulphate  of 
soda  then  undergoes  the  second  process  of  pulverizing 
the  same  (salt-cake)  and  heating  it  with  pulverized 
chalk  and  charcoal.  The  product  is  called  black-ash. 
By  lixiviation  and  evaporating  down  the  solution  (the 
heated  air  passing  over  a  leaden  pan  containing  the 
liquid)  and  calcining  afterwards  the  residue,  the 
soda-ash  of  commerce  is  obtained.  It  contains  from 
from  forty-eight  to  fifty-six  per  cent,  of  pure  caustic 
soda,  combined  as  carbonate  and  hydrate,  the  re- 
mainder being  impurities,  consisting  generally  of 
sulphate,  sulphite  and  chloride.  If  soda-ash  be  dis- 
solved and  the  saturated  solution  allowed  to  stand, 
large  transparent  crystals  of  the  hydrated  carbon ate^ 
known  as  soda  crystals,  are  obtained.  These  are 
used  to  soften  water  for  washing  purposes. 

Carbonate  of  soda  also  occurs  in  certain  localities 


SILICA,  OR  SAND. 


315 


as  an  efflorescence  on  the  soil  and  in  the  beds  of 
dried  up  lakes. 

Silica  or  Sand,  Geologically,  Chemically  and 
Technically  Considered. 

[Read  before  the  Polyteclinic  Institute.] 

Sand  is  the  term  generally  applied  to  all  powdered 
stone,  but  pure  sand  consists  of  particles  of  quartz,  silex 
or  silica,  which  is  composed  of  silicon  and  oxygen  ; 
and  its  chemical  symbol,  under  the  new  atomic  weight 
given  to  silicon,  is  Si,  O^.  These  particles,  which 
are  more  or  less  rounded,  are  of  a  white,  gray  or 
grayish  red  color,  and  are  unquestionably  derived 
originally  from  a  compact  rock,  called  the  sandstone 
formation.  Sand  niay,  however,  be  granitic,  con- 
taining particles  of  felspar.  This  is  the  case  when  it 
has  not  been  exposed  to  atmospheric  agents  long 
enough  to  decompose  it.  Sand  consisting  of  angular 
grains  is  mostly  employed  for  mortar  or  building 
purposes.  The  rock  called  sandstone  is  made  up  of 
agglutinated  sand  or  pebl)les  and  fragments  of  the 
same.  It  may  be  a  siliceous,  granitic,  porphyritic, 
basaltic  or  calcareous  sandstone,  according  to  the 
material  which  occurs  with  it  in  nature :  and  it  may 
be  a  compact,  friable,  ferruginous  or  concretionary 
sandstone,  according  to  its  structure.  Again,  if  the 
sandstone  glistens  with  scales  of  mica,  it  is  called  a 


316 


SILICA,  OR  SAND. 


micaceous  sandstone;  if  much  clay  is  mixed  with  the 
sand,  it  is  called  an  argillaceous  sandstone ;  and  if 
this  contains  lime,  it  is  called  marly  sandstone.  If 
the  quartz  or  sand  peebles  are  rounded,  and  are  held 
together  in  a  C(mglomerate,  tlie  result  is  called  a 
pudding-stone ;  and  if  they  are  angular,  a  breccia. 

The  flexible  sandstone,  or  itacolumite,  is  a  schistose 
quartz  rock. 

Buhrstone  is  a  cellular  siliceous  rock. 

The  millstone,  or  gritrock,  is  composed  of  siliceous 
pebbles. 

Siliceous  schist  is  a  flinty  quartz  rock. 

Jasper  rock  is  likewise  a  flinty  siliceous  rock. 

Obsidian  volcanic  glass,  or  pumicestone,  pitchstone, 
pearlstone,  are  all  siliceous  or  sandy  rocks,  having  a 
volcanic  origin. 

Sand,  if  transparent,  bears  the  name  of  quartz,  the 
constituent  of  a  great  many  rocks,  of  both  the  primi- 
tive and  new^er  formations.  Quartz  crystallizes  in 
six  sided  prisms,  with  no  apparent  cleavage,  of  all 
degrees  of  transparency  and  opacity,  and  of  all  colors, 
from  white  and  yellow  green  to  black,  with  inter- 
mediate amethystine,  rose  and  smoky  tints.  Pure 
pellucid  quartz  is  called  rock  crystal,  or  pure  silica. 

Quartz  is  infusible  before  the  blow-pipe,  but  when 
heated  with  soda,  fuses  easily  to  a  glass.  If  quartz 
has  colored  bands,  it  is  called  agate,  and  without 
bands  or  clouds,  it  is  chalcedony.    When  massive,  of 


SILICA,  OK  SAND. 


3ir 


dark  and  dull  color,  with  translucent  edges,  it  is 
called  flint ;  if  with  a  splintery  fracture,  it  is  horn- 
stone,  like  the  Arkansas  whetstone.  When  it  is  still 
more  opaque,  or  black,  it  is  the  Lydian  stone  or 
basanite ;  of  a  dull  red,  yellow^  or  brown  color,  and 
opaque,  it  is  jasper;  when  in  aggregated  grains,  it  is 
called  quartzite,  and  when  in  loose,  incoherent  grains, 
it  is  the  ordinary  sand,  which  is  frequently  trans- 
parent. Sandstone  belongs  to  all  ages,  from  the 
lower  Silurian  to  the  most  recent  period,  but  the  azoic 
rocks,  which  are  nearly  all  crystalline,  contain  some 
sandstone;  and  the  metamorphic,  which  are  the  most 
ancient  rocks,  and  comprise  granite,  gneiss  and  sye- 
nite, consists  largely  of  quartz.  Certain  dark  red 
sandstone  known  as  the  freestone  of  New  Jersey 
and  Connecticut,  and  the  general  term,  new  red  sand- 
stone is  applied  to  this  formation,  which  is  more 
recent  than  coal,  while  the  old  red  sandstone  lies 
below  the  coal,  and  above  the  great  laurentian  for- 
mation. Freestone  is  an  excellent  building  material ; 
in  New  York  it  is  used  more  than  any  other  stone. 
Trinity  church,  in  Broadway,  and  many  other  public 
and  private  buildings,  serve  as  examples ;  also  the 
greater  part  of  the  flagstones  which  are  brought  to 
this  city  from  Connecticut. 

The  green  sand  of  New  Jersey,  which  has  for  the 
last  thirty  years  enhanced  the  agricultural  prosperity 
of  the  lands  of  that  State,  and  which  belongs  to  the 


318 


SILICA,  OR  SAND. 


cretaceous  formation,  is  a  sandstone  containing  iron 
and  potash. 

A  short  description  may  prove  interesting: 
Ages  and  ages  ago,  in  the  mists  of  geological  anti- 
quity, an  ocean  lapped  the  margin  of  the  land  that 
extends  from  the  first  to  the  second  city  of  this  conti- 
nent. The  line  that  connects  New  York  and  Phila- 
delphia, when  straight  drawn,  will  be  seen  to  cross 
the  Delaware  River  at  its  eastermost  angle,  just  south 
of  Trenton.  In  the  period  referred  to,  such  a  line 
would  have  stretched  mostly  on  dry  land;  but  for  a 
part  of  the  distance  it  would  have  crossed  friths  and 
arms  of  the  sea,  and  broad  marine  swamps  and  mead- 
ows and  lagoons,  then  growing  rank  with  strange 
flora.  It  would  have  passed  over  broad  reaches  of 
warm  shoal  water,  in  which  huge  saurian  reptiles 
disported,  and  along  oozy  and  slimy  beds,  where 
great  turtles  were  sleeping.  Enormous  sharks,  also, 
darted  after  their  prey  through  waters  that  teemed 
with  scaly  life.  Down  at  the  bottom  of  this  ancient 
sea  there  were  myriads  of  minute  creatures,  of  shape 
and  in  size  not  unlike  a  tobacco  seed,  only  a  step 
advanced  from  vegetable  life  in  their  development 
and  habits.  So  low  were  they  in  the  scale  of  being 
that  the  naturalist  still  expresses  a  doubt  whether 
they  had  higher  than  a  vegetable  life.  But  minute, 
humble  and  beyond  the  ken  of  any  eye  but  the  All- 
seeing,  as  were  these  microscopic  atoms, — these  tiny 


SILICA,   OR  SAND. 


319 


animalcules — these  many  chambered  organisms,  they 
were  in  their  way  vastly  more  useful  than  the  giant 
reptiles  that  swam  over  them,  and  sprawled  in  the 
mud  through  which  these  little  shells  were  dispersed. 
For  now  that  all  this  dim  and  ancient  life  is  exhumed 
from  its  geological  grave,  now  when  the  spade  of  the 
laborer  throws  up  clay,  and  shell,  and  mud,  and  claw 
and  tooth  from  the  cool,  sunless  depths  where  they 
have  slumbered,  lieaven  knows  iiow  long,  we  find 
that  these  mites  and  pin-heads  of  the  old  ocean  have 
left  us  a  broad,  deep  and  exhaustless  bed  of  material, 
as  valuable  in  its  way  as  the  vein  of  silver  in  the  hill, 
or  the  stratum  of  coal  in  the  mountain  side.  The 
greatest  of  the  natural  laws  are  few  and  simple.  The 
sun  is,  and  ever  has  been,  the  grand  source  of  light. 
Afar  back  in  those  cycles,  compared  with  which  the 
period  of  human  history  is  as  the  span  of  a  man's 
hand  in  contrast  with  the  breadth  of  a  continent^ 
sunlight  was  drawing  carbon  from  the  air,  and  build- 
ing, cell  by  cell  and  foot  by  foot,  great  tropical 
forests,  rich  in  every  form  of  vegetable  life.  By 
crashes  and  earthquakes,  the  date  and  extent  of 
which  can  never  be  estimated  by  human  geology, 
these  forests  with  all  the  opulence  of  their  vegetable 
glory  were  plunged  into  fathomless  pits,  overwhelmed 
with  mountains  of  earth  and  stone,  and  deluged  with 
vast  avalanches  of  mud.  Compressed  by  the  mass 
above  and  roasted  by  the  central  fires,  these  ancient 


^20 


SILICA,  OR  SAND. 


forests  were  converted  into  coal  measnres,  and  now 
we  drive  our  millions  of  spindles,  we  speed  across 
oceans,  we  span  continents,  we  drive  printing  presses, 
and  light  our  studies  with  carbon  separated  so  long 
ago  by  the  great  Alchemist,  and  stored  in  this  mys- 
terious way  for  the  use  of  unborn  millions  of  men. 
In  the  same  way  great  magazines  of  plant-food  have 
been  prepared  by  the  action  of  obscure  animal  life, 
and  by  similar  convulsions  or  slow  upheavals,  gar- 
nered up  for  a  future  agriculture. 

Long  and  careful  research  may  eventually  disclose 
the  precise  contour  of  this  ancient  sea-shore.  All  we 
now^  know,  is  that  a  substance  we  call  greensand 
occurs  throughout  the  cretaceous  belt  of  I^ew  Jersey. 
Draw  a  line  from  the  shore  just  south  of  Long  Branch 
to  New  Brunswick  and  it  will  run  across  the  creta- 
ceous bed  at  right  angles,  and  cut  three  distinct  beds 
or  layers  of  greensand.  The  marl  or  greensand  was 
probably  deposited  at  three  Epochs,  and  the  dilferent 
layers  repr-esent  three  periods  of  change,  by  which 
these  beds  became  submerged  and  covered  with  sand. 
Of  course  the  depth  of  water,  the  number  and  size  of 
the  organic  creatures,  and  the  amount  of  vegetable 
debris  was  different  at  various  points  along  this 
margin.  Where  a  harbor  was  deep,  concave  and 
land-locked,  the  deposit  of  mud  would  be  deep  and 
even.  The  little  polythalmia  would  multiply  and 
work  undisturbed.    When  such  a  bed  became  over- 


SILICA,  OR  SAND. 


321 


whelmed  with  a  mass  of  ocean  sand,  we  should 
expect  to  find  a  layer  many  feet  thick,  alike  in  all  its 
parts,  and  equally  rich  in  animal  remains.  This  is 
the  description  of  the  best  marl  heds  as  yet  uncov- 
ered in  New  Jersey.  In  waters  that  were  shoaler  or 
nearer  the  margin  and  overhuno;  with  forests,  or 
where  rivers  brought  down  a  mixed  debris  and  some- 
times flung  it  rudely  and  sometimes  laid  it  quietly 
upon  the  bottom  of  a  bay  or  lagoon,  we  should  expect 
a  chaotic  and  irregular  deposit.  Tliis  is  just  the  con- 
dition disclosed  by  the  spade,  the  borer  and  the 
excavator  in  the  marl  beds  of  New  Jersey.  Marl  as 
a  deposit  in  the  earth,  having  more  or  less  value  as 
a  fertilizer,  occurs  in  many  parts  of  the  world,  and 
has  been  in  use  by  the  farmers  of  England  and  France 
for  several  generations.  But  the  New  Jersey  deposit 
is  quite  different  from  common  marl,  and  much  more 
valuable.  By  the  word  marl  the  English  geologist 
understands  a  bed  of  clay  or  alumina  mixed  with 
sand,  with  considerable  carbonate  of  lime.  On  soil& 
requiring  alumina,  as  most  sandy  lands  and  where 
lime  is  not  abundant,  such  marl  is  a  useful  a[)plica- 
tiou  and  pays  for  transporting  short  distances.  But 
it  is  the  greensand,  the  result  of  the  life  and  death  of 
myriads  of  small  sea  animals,  that  gives  New  Jersey 
marl  its  peculiar  value,  and  makes  it  not  only  a  local 
but  a  commercial  fertilizer. 

Greensand  is  found  in  many  other  parts  of  the 


322 


SILICA,  OE  SAND. 


world,  and  especially  along  the  Atlantic  coast.  Pro- 
fessor Bailey  examined  a  specimen  taken  from  the 
depth  of  140  feet  in  an  artesian  well  at  Charleston  ; 
and  the  soundings  of  the  Coast  Survey  brought  up 
from  the  depths  of  the  ocean,  in  and  near  the  Gulf 
Stream,  a  substance  which  w^as  found  identical  in 
appearance  with  the  contents  of  the  Squankum  beds. 

Ehrenberg,  found  the  rounded  particles  to  be 
the  casts  of  minute  shells.  The  shells  themselves 
have  disappeared,  but  their  material  form  has  been 
retained  in  the  more  durable  silicate  of  iron.  This 
silicate  of  iron  is  mixed  with  phosphate  of  lime 
or  phosphoric  acid.  The  latter  is  no  doubt  of  animal 
origin.  Sea  water  and  acids  from  the  soil  have  eaten 
away  some  of  the  carbonate  of  lime,  but  the  phos- 
phoric acid  remains  and  gives  the  deposit  its  greatest 
agricultural  value. 

The  cretaceous  belt  of  New  Jersey,  in  most  parts 
of  which  greensand  is  found,  extends  from  a  line  con- 
necting Trenton  and  New  Brunswick,  on  the  north- 
west, to  a  line  nearly  parallel  with  this,  but  about  ten 
miles  south-east,  connecting  the  mouth  of  Shark 
River  (a  little  south  of  Long  Branch)  with  Salem  on 
the  Delaware.  The  region  thus  bounded  on  the 
north  and  south  extends  from  Raritan  Bay  to  Dela- 
ware River,  being  nearly  fifteen  miles  wide  on  the 
Atlantic  side  of  the  State  and  not  over  five  miles 
wide  on  the  Delaware  side.    There  are  three  beds  or 


SILICA,  OR  SAND. 


323 


layers  of  greeiisand  in  the  cretaceous  belt,  but  the 
upper  or  newest  deposit  runs  over  into  the  tertiary 
or  sandy  formation  that  takes  in  all  Jersey  south  of 
the  marl  beds.  The  general  bearing  or  strike  of 
these  beds  is  north  fifty -four  degrees  east,  and  they 
all  dip  or  run  away  under  the  sandy  deposit  above 
them,  getting  twenty -five  or  thirty  feet  lower  each 
mile  as  one  passes  to  the  southeast.  The  region  over 
which  these  beds  may  be  reached  by  digging  from 
three  to  fifty  feet,  is  ninety  miles  in  length  and  on 
an  average  about  seven  or  eight  in  width,  and  its  area 
is  nine  hundred  square  miles.  The  strata  themselves 
are  fifteen  to  thirty  feet  thick.  Near  streams  the 
sand  and  clay  that  covers  these  beds  have  been  washed 
away  ;  hence  the  marl  is  discovered  by  looking  along 
the  banks  of  the  brooks  that  run  from  the  cretaceous 
lands,  eitlier  northwest  into  the  Delaware,  or  south- 
east into  the  Atlantic.  In  places,  the  marl  is  within 
three  or  four  feet  of  the  surface,  so  by  removing  a 
slight  top  layer  of  sandy  loam  the  bed  may  be  reached . 
but  generally  a  stratum  several  feet  thick,  of  spurious 
or  useless  marl  covers  the  greensand. 

As  already  stated,  sand  and  quartz  are  pure  silica; 
still  there  is  no  mineral  that  assumes  so  many  forms 
and  colors  as  quartz,  though  none  is  more  easily  dis- 
tinguished.   Ite  characteristic  features  are : 

1.  Its  hardness,  which  is  from  6.5  to  7,  enabling  it 
to  scratch  glass  with  facility. 


324 


SILICA,  OR  SAND. 


2.  Its  iiifnsibility ;  when  heated  alone  before  the 
blow-pipe  it  does  not  melt. 

3.  Its  iTisol ability,  as  it  is  not,  like  limestone, 
attacked  by  the  strong  mineral  acids. 

4.  Its  want  of  cleavage,  which  has  been  mentioned 
above.  This  is  one  of  the  lirst  characteristics  of 
quartz, 

5.  Its  crystalline  character,  occurring  mostly  in 
in  six-sided  prisms,  more  or  less  modified  and  termi- 
nated. 

6.  Its  low  specific  gravity  of  2.5  to  2.7,  is  an  un- 
failing distinctive  character  of  quartz. 

Rock  crystal  is  a  pure  pellucid  quartz,  and  was 
known  by  the  ancients  under  the  name  of  crystallos^ 
meaning  ice.  It  is  used  for  optical  instruments, 
spectacle  glasses,  and  cut  with  facets,  for  jewelry. 
The  crystals  are  often  called  real  California  diamonds. 
In  ancient  times  it  was  cut  into  cups  and  vases,  and 
it  is  said  that  on  hearing  of  his  final  overthrow,  Nero 
dashed  into  pieces  a  cup  which  was  worth  $3,000. 
To  this  class  of  quartz  belongs  the  finest  ornaments 
which  adorn  the  palaces  of  ancient  and  modern  times  \ 
and  some  forms,  such  as  amethyst,  rose  quarts,  false 
topaz ^  smoky  quartz^  known  as  Scotch  pebbles,  or 
cairngorm,  the  favorite  ornaments  of  the  sportsmen 
of  the  Highlands,  are  used  as  jewels.  • 

Milky  quartz,  or  greasy  quartz. 

Prase  is  of  leek  green  color. 


SILICA,  OR  SAND. 


325 


Avanturine^  more  commonly  known  as  gold-stone, 
is  a  quartz  spangled  throughout  with  scales  of  golden 
yellow  mica,  although  tlie  artificial  imitation  looks 
more  beautiful  than  natural  stone. 

Chalcedony  is  a  translucent  variety  of  quartz,  which 
often  lines  the  cavities  of  other  rocks,  and  in  the  form 
of  stalactites,  which  are  then  called  icicles  of  chalce- 
dony, and  forming  grottoes  several  feet  in  diameter. 
We  find  such  in  the  Faroe  Islands,  in  Florida,  and  in 
many  volcanic  rocks,  probably  owing  to  siliceous 
waters  filtering  at  some  period  through  the  rock,  and 
deposited  by  their  concentration.  Chrysoprase  is  but 
an  apple-green  chalcedony. 

The  earnelian  is  a  bright  red  chalcedony,  of  a 
clear,  rich,  flesh-colored  tint ;  it  is  a  great  favorite 
with  the  Japanese. 

The  sard  is  a  deep  brownish  red  chalcedony. 

Agate  is  a  variegated  chalcedony,  and  its  colors  are 
distributed  in  clouds,  spots,  or  consecutive  lines, 
which  may  be  straight,  circular  or  zigzag  forms. 
AVhen  the  outlines  are  angular,  resembling  a  fortifi- 
cation, it  is  called  a  fortification  agate ;  if  dendritic 
or  moss-like  delineations,  arising  from  disseminated 
oxide  of  iron  or  manganese,  it  is  called  mocha  stone 
or  moss  agate.  The  color  of  agate  is  much  darkened 
by  boiling  the  stone  in  oil,  and  then  dropping  it  into 
sulphuric  acid  ;  a  little  oil  is  absorbed  by  some  of  the 
layers  and  the  acid  blackens  or  chars  it. 

14 


326 


SILICA,  OR  SAND. 


The  onyx  is  an  agate,  where  the  colors  are  arranged 
in  flat  horizontal  layers,  formed  usually  of  light  clear 
brown  and  an  opaque  white.  When  this  stone  is  a 
sard  and  white  chalcedony  in  alternate  layers,  it  is 
called  sardonyx. 

The  antique  cameos  and  sculptured  small  orna- 
ments from  onyx  are  well  known,  such  as  the  Man-' 
tuan  vase,  at  Brunswick,  seven  inches  high  and  two 
and  o]ie-half  inches  broad,  representing  a  cream  pot, 
and  cut  from  a  single  stone  ;  having  white  and  yellow 
groups  of  raised  figures,  representing  Ceres  and  Trip- 
tolemus  in  search  of  Proserpine. 

The  cat's  eye  is  a  greenish  gray  translucent  chal- 
cadony,  having  an  opalescence  or  reflection,  like  the 
eye  of  a  cat,  w^hen  cut  with  a  spheroidal  surface, 
probably  owing  to  filaments  of  asbestos. 

The  jasper  is  a  dull  red  siliceous  rock,  containing 
some  clay  and  yellow  or  red  oxyd  of  iron,  and  has  all 
the  varieties  of  riband,  Egyptian  resin  and  porcelain, 
all  assuming  a  high  lustre  and  polish. 

Bloodstone  or  heliotrope,  is  of  a  deep  green  color, 
slightly  translucent,  and  containing  red  spots,  resem- 
bling red  drops  of  blood  ;  many  superstitious  people 
have  attached  much  importance  to  these  red  spots, 
and  a  bust  of  Christ  in  the  Paris  museum  represents 
quite  natural  blood  drops. 

The  lydian,  or  touchstone,  is  a  velvet  black,  sili- 
ceous stone,  or  flinty  jasper,  which  is  used  on  account 


SILICA,  OR  SAND. 


327 


of  its  hardness  and  black  color  for  trying  the  purity 
of  the  precious  metals.  This  is  done  by  comparing 
the  color  of  the  tracing  left  on  it  with  that  of  an  alloy 
of  known  character. 

Petrified  wood,  called  also  silicified  wood,  contain- 
ing the  texture  of  the  original  wood,  which  when 
sawn  across  and  polished  is  remarkably  beautiful. 

Quartz  crystals  are  often  found  inclosed  with  other 
minerals,  such  as  rutile,  asbestos,  actinolite  and 
topaz,  oxyd  of  iron,  tourmaline,  chlorite  and  anthra- 
cite coal ;  those  containing  the  rutile  look  as  if 
needles  or  fine  hairs  passed  through  them  in  every 
direction,  and  when  cut  for  jewelry,  pass  by  the  name 
of  love's  arrows,  oy  fleches  cT amour. 

The  opal,  one  of  the  most  fashionable  jewels,  is 
silica,  with  some  water ;  it  exhibits  internal  reflec- 
tions of  rainbow  colors,  and  forms  a  gem  of  rare 
beauty ;  it  is  usually  cut  with  a  convex  surface. 
Among  the  varieties  of  opal  are  fire-opal  or  girasol ; 
it  has  a  yellow,  bright  hyacinth,  or  fire-red  reflections. 
The  common  or  semi-opal,  has  a  milky  opalescence, 
but  does  not  reflect  a  play  of  colors. 

Hydrophane,  cacholong,  hyalite,  menilite,  wood 
opal,  jasper,  siliceous  sinter,  pearl  sinter  and  fabasheer, 
all  belong  to  the  same  class  of  silicious  minerals,  and 
are  of  more  interest  to  the  mineralogist  than  to  the 
general  reader. 

Among  all  the  discoveries  relating  to  the  arts,  none 


328 


SILICA,  OE  SAND. 


exceed  in  importance  and  usefulness  to  mankind,  the 
art  of  glass  making.  G-lass  is  a  chemical  combina- 
tion of  sand  and  alkali  or  alkaline  earth,  heated  to 
fusion,  and  presenting  after  fusion  a  transparent  and 
hard  body.  The  benefits  conferred  by  it  upon  all 
classes  of  human  society  have  been  immense  ;  the 
spectacle,  the  microscope,  the  telescope,  and  spectro- 
scope, have  showered  incalculable  blessings  upon  the 
world,  and  there  are  probably  still  greater  discoveries 
in  store  for  us.  The  history  of  the  manufacture  of 
glass  may  be  traced  from  the  present  time  through 
that  of  the  Romans  and  Phoenicians,  to  the  Egyp- 
tians, some  of  whose  productions  remain  to  this  age. 
The  art  flourished  in  Tyre,  in  Alexandria,  and  lastly 
in  Rome  ;  and  after  being  depressed  for  some  ages, 
again  revived  under  the  Venetians,  who  transmitted 
the  improved  art  to  the  rest  of  the  nations  of  Europe. 
Pliny  relates  that  glass  was  first  discovered  by  acci- 
dent in  Syria,  at  the  mouth  of  the  river  Belus,  by 
certain  merchants  driven  thither  by  the  fortune  of 
the  sea  and  obliged  to  remain  there  and  dress  their 
victuals  by  making  a  fire  in  the  ground.  There 
being  great  abundance  of  the  herb  kali  in  that 
vicinity,  the  ashes  of  the  plant,  mixed  and  incor- 
porated with  the  sand,  formed  glass. 

Boerhave  says,  that  the  art  of  glass  making  is  of 
ancient  origin,  being  first  cultivated  in  Egypt,  while 
glass  was  rendered  malleable  in  the  age  of  Tiberius, 


SILICA,  OR  SAND. 


329 


and  is  now  manufactured  in  the  greatest  perfection. 
It  is  one  of  the  most  useful  arts  to  mankind  ;  for  by 
it  in  conjunction  with  the  grinder's  help,  we  obviate 
the  natural  infirmities  of  the  eye.  Without  it,  old 
people,  and  tliose  whose  optic  nerves  are  affected, 
would  be  debarred  the  knowledge  of  reading  letters 
or  books,  and  would  be  unable  to  sit  within  doors,  or 
in  a  coach  or  ship,  and  see  all  things  clearly  around 
them,  yet  without  being  exposed  to  the  scourging 
heat  or  freezing  cold,  or  being  annoyed  with  the  east 
wind,  or  the  ingress  or  extraneous  filth.  Pure  glass 
will  scarcely  receive  any  stain,  and  is  easily  cleansed 
again.  Although  the  essential  constituents  of  glass 
are  silex  and  alkali,  it  generally  contains  other  sub- 
stances, such  as  metallic  oxides,  which  are  designed 
to  modify  its  external  character  of  hardness,  fusi- 
bility, brilliancy,  color  and  transparency.  Many 
kinds  of  glass  contain  either  potash  or  soda;  the  first 
is  not  much  employed  by  the  manufacturers  of  com- 
mon glass.  Some  kinds  contain  lime  and  oxide  of 
lead  and  alumina  and  oxide  of  iron  ;  the  two  latter 
are  however  mere  accidental  impurities.  The  follow- 
ing constitute  the  principal  materials  of  glass : 

1.  Silex,  or  sand,  which  is,  as  already  stated,  very 
abundant  on  the  globe  ;  the  sand  mostly  employed  is 
the  white  sand,  either  obtained  from  the  disintegrated 
sandstone  rocks,  which  are  numerous  in  the  United 
States,  as  in  Missouri,  near  St.  Genevieve,  and  Berk- 


330 


SILICA,  OR  SAND. 


eliire  county,  Mass. ;  or  from  the  river  sand  which  is 
found  in  large  beds  of  white  sand  at  Maurice  river, 
in  Kew  Jersey  and  Florida.  Drift  sand  is  brought 
by  the  winds  from  the  sea  coasts  or  deserts,  but 
mostly  from  the  lower  sands  of  sea  shores,  as  we  find 
them  for  100  miles  on  the  Long  Island  shore ;  this 
sand  when  washed  forms  a  good  sand  for  glass. 

The  infusorial  deposits  of  the  siliceous  shells,  called 
the  diatoms^  which  form  immense  deposits  both  in- 
land and  on  the  coasts,  yield  a  good  material  for  the 
manufacture  of  glass. 

2.  Alkali.  If  potash  is  used,  the  purified  pearlash 
is  employed,  particularly  for  plate  glass  and  the  fewer 
kinds  of  crown  glass,  as  also  soda  ash^  which  is  the 
carbonate  of  soda,  is  also  used  for  the  better  qualities 
of  glass  ;  while  sulphate  of  potash,  glauber  salt,  salt- 
cake  or  common  salt  are  employed  for  common  glass. 

3.  Lime,  either  as  air-slaked,  quick-lime,  or  as  car- 
bonate of  lime,  such  as  marble  or  chalk,  is  used  for 
the  manufacture  of  green  glass. 

4.  Oxide  of  lead,  or  litharge,  or  red  lead,  are  use- 
fully employed  in  the  manufacture. 

5.  Certain  materials  are  used  for  improving  or 
purifying  the  glass,  such  as  thebinoxideof  manganese, 
nitre,  arseneous  acid  and  white  arsenic.  Oxide  of 
lead,  in  the  form  of  minium,  is  principally  used  in 
flint  glass,  as  it  increases  its  brilliancy,  the  purity  of 
its  color  and  the  power  of  its  refraction.   The  binoxide 


SILfCA,  OR  SAND. 


331 


of  manganese,  was  formerly  known  as  glass-maker's 
soap ;  its  effect  is  ascribed  to  tlie  facility  with  which 
it  gives  np  its  oxygen,  which  combines  with  the 
coloring  principles  and  destroys  them.  In  other 
words,  it  converts  the  protoxide  of  iron,  which  would 
giv^e  the  glass  a  dark  green  color,  into  a  sesquioxide, 
which  is  of  higher  oxydation  and  which  leaves  the 
glass  clearer. 

Borax  and  boracic  acid,  as  also  the  borate  of  lime, 
called  Hayesine,  from  Peru,  are  like  the  Chili  salt- 
petre, very  useful  and  powerful  agents  for  accelerating 
the  fluxing  of  the  silex. 

The  silex  mostly  used  in  England  is  sea  sand,  and 
not  river  sand,  as  is  extensively  used  in  the  United 
States ;  it  consists  chiefly  of  quartz,  and  the  finest 
qualities  are  obtained  from  Alum  Bay,  in  the  Isle  of 
Wight,  and  from  near  Lyon,  on  the  coast  of  Norfolk  ; 
the  black  flint,  when  raised  to  a  red  heat,  and  plunged 
in  cold  water,  is  frequently  used,  and  probably  gave 
the  name  to  a  species  of  glass,  flint  glass  or  crystal 
glass. 

The  manufacture  of  glass  is  divided  into  several 
classes  : 

A.  Window  glass,  which  includes, 

1.  Crown  glass. 

2.  Sheet  glass. 

3.  Brown  plate,  silvered  or  unsilvered. 

4.  Colored  sheet,  pot  metal  or  flashed. 


332 


SILICA,  OR  SAND. 


B.  Painted  and  other  kinds  of  ornamental  window 
glass. 

C.  Cast  plate  glass. 
a.  Rougli  plate. 
h.  Pressed  plate. 
c.  Rolled  plate. 

D.  Bottle  glass. 

1.  Ordinary  bottle  glass. 

2.  Moulded  bottle  glass. 

3.  Medicinal  bottles. 

4.  Tubing. 

E.  Glass  for  chemical  and  philosophical  purposes, 
retorts,  reservoirs,  large  water  pipes,  etc.,  etc. 

F.  Flint  or  crystal  glass,  with  or  without  lead; 
white,  colored,  ornamented,  for  table  ware,  etc. 

1.  Blown. 

2.  Moulded  and  pressed. 

3.  Cut  and  engraved. 

4.  Reticulated  and  spun  with  a  variety  of  colors, 
incrusted,  flashed,  enameled  of  all  colors,  opalescent, 
imitation  of  alabaster,  gilt,  gelatinized,  silvered. 

5.  Glass  mosaic,  miliflori,  aventurine  and  Vene- 
tian glass  weights. 

6.  Beads,  and  imitation  of  pearls,  etc. 

Y.  Chandeliers,  candlesticks,  and  lamp  aparatus. 

G.  Optical  glass,  flint  and  crown. 

1.  Rough  disks  of  flint  and  crown,  to  make 


SILICA,  OR  SAND. 


333 


lenses  for  telescopes,  microscopes,  stereoscopes,  spec- 
troscopes, daguerreotype  and  calotype  apparatus. 

2.  Flint  and  crown,  blown,  or  cast  in  plates  for 
the  optician. 

3.  Fine  glass  for  microscopes. 

4.  Kefractive  apparatus,  prismatic  lenses  for 
lighthouses. 

The  above  classification  was  made  at  the  London 
universal  exhibition  of  1851.  Another  classification 
is  made  in  the  following  kinds,  according  to  their 
constituent  materials : 

1.  The  soluble  glass,  silicate  of  soda  or  potash,  or 
both  alkalies  combined  with  silica. 

2.  Bohemian  glass,  a  silicate  of  potash  and  lime. 

3.  Crown,  or  spread,  a  silicate  of  soda  and  lime. 

4.  Plate,  a  silicate  of  soda  and  lime  cast  into  plates. 

5.  Bottle,  a  silicate  of  potassa,  lime,  alumina  and 
oxide  of  iron. 

6.  Crystal,  silicate  of  potash  and  oxide  of  lead. 

7.  Flint  contains  more  lead  than  the  last. 

8.  Strass,  or  paste,  contains  still  more  lead  than 
flint. 

9.  Enameled  and  colored  glass,  from  all  the  above 
except  No.  1  and  No.  5. 

An  excess  of  alkali  is  often  used  in  order  to  obtain 
a  more  fusible  glass,  but  such  glass  is  more  readily 
acted  upon  by  acids ;  even  when  water  is  boiled  in  it, 
it  will  readily  convert  red  litmus  to  blue,  on  account 


334 


SILICA,  OR  SAND. 


of  its  alkali ;  caustic  alkali  attacks  glass  by  dissolving- 
the  silica,  and  fluoliydric  acid  decompose  glass  readily. 

As  regards  the  physical  characters  of  glass,  it  may 
be  remarked  that  all  glass  is  fusible,  but  the  temper- 
ature for  different  kinds  is  different ;  oxide  of  lead,  or 
a  larger  amount  of  alkaline  silicate  imparts  more 
ready  fusibility,  and  a  similar  effect  is  produced  by 
borax.  Bottle  glass,  containing  oxide  of  iron  and 
aluminum  and  less  alkali,  is  more  difficult  of  fusion 
than  other  kinds.  When  melted  glass  is  cooled  it  is 
perfectly  flexible  and  plastic  before  it  is  cooled  down 
to  rigidity  ;  the  softer  kinds,  such  as  flint  or  borax 
glass,  when  heated,  begin  to  be  plastic  below  a  red 
heat ;  when  in  the  plastic  state  pieces  w^ill  unite 
together  as  firmly  as  if  they  were  melted  together. 
When  glass  is  much  softened  by  heat,  it  may  be 
readily  drawn  out  into  rods  or  tubes,  or,  if  passed 
around  a  revolving  wheel,  into  minute  flexible  threads, 
called  thin  glass  hairs,  and  these  properties  causes  the 
glass  to  be  formed  into  numberless  shapes  demanded 
by  the  wants  of  civilized  life. 

Glass  conducts  heat  so  imperfectly,  that  the  end  of 
a  rod  heated  to  whiteness  may  be  held  with  safety  by 
the  hand,  within  an  inch  or  two  of  the  heated  end  ; 
the  bad  conducting  power  of  glass,  combined  with 
the  cohesive  force  of  its  particles,  gave  rise  to  the 
manufacture  of  Prince  Rupert's  drops,  which  are 
pear-shaped  pieces  of  glass,  with  a  long  thin  stem, 


SILICA,  OR  SAND. 


335 


made  by  dropping  melted  glass  into  water ;  the  bulb 
may  be  struck  without  injury,  but  if  the  smallest 
particle  of  the  stem  be  broken  off,  the  whole  drop 
flies  into  powder  with  explosive  noise  and  violence, 
owing  to  the  bad  conducting  power  of  glass,  com- 
bined with  the  cohesive  force  of  its  particles.  Glass 
expands  when  heated  and  contracts  on  cooling,  which 
must  be  done  very  slowly,  in  order  to  allow  the 
particles  to  come  uniformly  close  together.  If  sud- 
denly cooled  by  dropping  melted  glass  into  water, 
the  outside  suddenly  assumes  the  rigid  and  more 
contracted  form,  while  the  interior  is  still  soft  and 
expanded  from  the  bad  conducting  power  of  the  glass. 
When  thoroughly,  cooled,  the  interior  must  still 
retain  the  expanded  state,  so  contrary  to  its  cohesive 
force  at  common  temperature,  and  when  the  cohesion 
of  the  outer  layer  is  in  the  least  disturbed,  as  by  a 
scratch  or  slight  fracture,  the  whole  of  the  cohesive 
force  exerts  its  power  to  fracture  the  entire  mass. 
From  this  fact,  it  is  necessary  to  cool  more  slowly 
than  can  be  done  in  the  air  and  the  process  of  anneal- 
ing is  indispensable.  This  consists  in  placing  a  glass 
vessel,  as  soon  as  made,  and  while  still  hot  in 
one  end  of  a  long  annealing  oven,  with  a  fire 
at  this  end  and  gradually  pushing  to  the  further 
or  cold  end  of  the  oven  ;  the  particles  of  the 
interior  and  exterior  have  then  time  to  arrange 
themselves  uniformly  according  to  their  cohesive 


836 


SILICA,  OR  SAN-D. 


force  at  each  point  of  temperature,  until  they  be- 
come perfectly  rigid. 

Glass  is  very  elastic,  as  is  easily  shown  by  any  strip 
of  window  glass,  but  more  strikingly  by  hollow  balls 
suspended  by  strings.  On  playing  with  your  lingers 
on  the  windows,  the  harmonious  sounds  indicate  their 
elasticity.  A  glass  harmonicon  consists  of  small  strips 
of  window  glass  of  different  sizes,  suspended  on  par- 
allel strings.  They  may  be  graduated  to  any  scale ; 
goblets  of  various  sizes  are  also  sometimes  employed 
in  a  similar  manner,  and  are  made  to  vibrate  by  pass- 
ing the  moistened  finger  around  their  upper  edges. 

As  has  been  stated,  one  of  the  various  kinds  of 
glass  is  the  soluble  glass ^  or  silicate  of  soda  or  pottassa, 
or  both  combined,  and  on  account  of  an  excess  of 
alkali,  has  become  a  soluble  salt.  It  is  termed  also 
water  glass,  and  has  the  formala,  2  KO.  or  Na  03, 
Si  O^,  according  to  the  old  notation.  The  uses  of 
silicate  of  soda  are  for  the  application  to  wood  and 
textile  fabrics,  as  a  paint  and  substitute  of  dunging 
salt  in  calico  printing,  have  been  fully  discribed  in 
the  proceeding  treatise. 

The  Bohemian  glass  is  manufactured  largely  in 
Bohemia,  from  100  parts  of  silica,  purified  pearlash, 
sixty  parts,  and  carbonate  of  lime,  sixteen  parts. 
These  three  substances  are  fritted  in  a  reverberatory 
oven  called  calcar,  and  while  still  red  hot,  thrown 
into  the  glass  pots,  already  in  a  glowing  heat,  and 


SILICA,  OR  SAND. 


337 


tliere  melted,  and  when  perfectly  liquid,  scooped  ont 
or  taken  out  with  an  iron  rod.  The  objects  of  fritting 
are  to  expel  moisture  and  carbonic  acid,  and  produce 
a  caking  of  the  materials,  which  facilitates  the  fusion. 
This  glass  is  employed  for  making  panes,  tumblers 
and  other  articles,  which  are  characterized  by  their 
beauty  when  compared  with  flint  and  crystal  glass. 
They  also  possess  greater  infusibility  and  resistance 
to  chemical  agents  ;  for  this  reason  it  has  become 
celebrated  and  indispensable  in  the  laboratories. 

The  vial  and  spread  glass  has  a  similar  composi- 
tion to  the  last  described,  and  contains  silica,  soda, 
lime  and  sometimes  potash  in  similar  proportions,  as 
before  ;  but  a  smaller  amount  of  soda  is  requisite  than 
of  potash,  because  soda  has  a  lower  equivalent.  For 
spread  or  common  window  glass,  a  considerable 
quantity  of  soda  is  used  in  order  to  flux  the  materials 
rapidly,  and  the  addition  of  salt  is  believed  to  clear 
the  glass. 

For  making  window  panes,  a  lump  of  melted  glass 
is  taken  out  of  the  pot,  blown  and  elongated  in  to  a 
pear,  then  blown  and  rolled  into  a  cylinder,  which  is  slit 
longtudinally  on  one  side  for  its  whole  length ;  it  is 
then  placed  on  the  smooth  hearth  of  the  flattening 
kiln,  with  the  slit  side  uppermost,  and  when  softened 
by  heat,  is  opened,  until  it  spreads  out  upon  the 
hearth,  a  flattened  sheet. 

Crown  glass  is  composed  of  materials  similar  to 


338 


SILICA,  OR  SAND. 


those  of  the  preceding  kind,  but  they  are  generally 
poorer;  to  100  parts  silica,  sixty  parts  soda  ash, 
eight  parts  potash,  ten  parts  lime,  four  parts  saltpeter 
or  nitrate  of  soda,  one-eight  part  of  white  arsenic  is 
thrown  in  the  melting  pot.  The  mixed  materials  are 
placed  in  a  furnace,  which  is  of  rectangular  construc- 
tion, containing  from  four  to  six  clay  pots,  of  the 
capacity  of  half  a  ton  of  glass,  and  is  now  quickly 
heated  ui)  to  the  melting  point.  When  the  tirst 
charge  is  melted  down,  the  next  is  tlirown  in,  and  so 
on  until  the  pot  is  sufficiently  tilled.  The  tempera- 
ture is  then  lowered  for  a  few  hours,  during  which 
some  of  the  foreign  matters  subside,  and  the  glass  all 
rises  to  the  top,  when,  after  raising  the  tire  a  little,  it 
is  skimmed.  It  is  called  crown  glass  on  account  of 
the  shape  it  assumes  when  broken  otf  from  the  coal 
formed  at  the  end  of  the  iron  rod  called  the  punto. 

Plate  glass  is  composed  of  100  parts  silex,  thirty- 
three  parts  carbonate  of  soda,  twenty  parts  carbonate 
of  lime,  and  a  very  small  proportion  of  paroxide  of 
manganese  ;  say  one-half  part.  This  glass  is  usually 
cast  into  large  plates,  for  mirrors  and  large  panes  ;  all 
materials  must  be  very  pure.  The  arrangement  for 
casting  the  ton  of  glass  into  the  forms  are  very  inter- 
esting, and  must  be  seen  personally,  at  St.  Gobin,  in 
France,  or  at  Eavenhead,  in  England,  to  be  appreci- 
ated. 

Bottle  glass  is  composed  of  the  coarsest  materials 


SILICA,  OR  SAND. 


339 


of  silex,  soda,  lime,  oxide  of  iron,  and  clay.  It  is 
generally  of  less  specific  gravity  than  any  other 
variety;  it  is  tougher  and  resists  chemical  action. 
In  New  Jersey,  green  sand  is  added  to  spread  glass^ 
for  beer  bottles,  etc.,  etc. 

Lead  glass  comprises  three  varieties,  crystal,  flint 
glass,  and  strass,  differing  in  the  pro|)ortions  of  lith- 
arge and  red  lead  they  contain  ;  it  may  be  shown 
that  crystal  glass  contains  but  little  oxide  of  lead,  in 
comparison  to  the  famous  paste  called  strass,  which 
contains  more  oxide  of  lead  than  silica.  The  crystal 
glass  is  composed  of  100  parts  of  silica,  ten  parts 
oxyd  of  lead,  thirty -five  parts  [)urifled  potash,  and 
thirteen  parts  cai'bonate  of  lime.  The  common  flint 
glass  contains  100  parts  silica,  sixty-six  parts  oxide  of 
lead,  twenty-six  parts  purifled  potash,  and  seven 
part  saltpeter.  Optical  glass  contains  100  parts 
silica,  100  parts  oxyd  of  lead,  twenty-three  parts 
purified  potash,  and  a  very  small  proportion  of  salt- 
petre and  borax.  Strass  contains  100  parts  silica,. 
133  parts  oxyd  of  lead,  and  thirteen  parts  purified 
potash.  The  dried  and  mingled  materials  are  then 
thrown  into  the  white-hot  melting  pots,  and  when 
full  of  melted  glass,  the  mouths  of  the  oven  are  closed. 
Some  heavy  combinations  of  lead  sink  to  the  bottom, 
while  the  salts,  which  will  not  incorporate  with  the 
glass,  rise  to  the  top  as  a  scum,  called  glass  gall  and 
sandiver.    The  greater  part  of  this  is  skimmed  off. 


340 


SILICA,  OR  SAND. 


Strass  is  the  basis  of  a  beautiful  glass,  and  was  in- 
vented in  the  seventeenth  century  by  a  man  named 
Strass,  of  Strasbiirgh,  who  first  conceived  the  import- 
ance of  imitating  the  real  gems  as  respects  their 
hardness,  specific  gravity,  and  refraction  of  light, 
and  the  w^hite  mass  obtained  by  his  receipt  has  pro- 
duced a  beautiful  base  for  imitating  the  diamond,  the 
rock  crystal,  and  the  white  topaz.  It  is  now  manu- 
factured in  large  quantities  in  France,  as  a  base  also 
for  the  production  of  all  other  colored  gems,  such  as 
ruby,  emerald,  sapphire,  amethyst,  aquamarine,  gar- 
net, chrysoprose,  opal,  hyacinth,  rubellite,  indigolite, 
or  blue  turmaline,  chrysolite,  turquoise,  lazulite,  and 
agate.  Although  the  properties  which  are  usually 
considered  as  constituting  excellence  in  glass  for 
ordinary  purposes  may  be  easily  obtained,  yet  in 
glasses  for  optical  instruments,  and  to  be  employed 
in  the  examination  of  objects  so  remote  and  so  min- 
ute as  to  require  the  most  undeviating  accuracy,  the 
difficulty  of  obtaining  the  metal  (or  the  mass)  suffic- 
iently free  from  the  defects  to  which  glass  is  incident, 
lias  until  a  late  period  baffled  every  attempt  to  pro- 
duce a  lens,  except  of  comparatively  small  dimen- 
sionns ;  although  purity,  anchangeableness  of  color, 
transparency,  and  a  certain  degree  of  refractive 
power  may  be  obtained,  but  perfect  uniformity  in 
the  structure  of  the  glass,  so  as  to  render  its  composi- 
tion absolutely  homogeneous  in  all  its  parts,  is  not  so 


SILICA,  OR  SAND. 


341 


easy  to  be  accomplished,  and  it  is  precisely  this 
quality  which  is  the" most  indispeiisible  in  the  manu- 
facture of  optical  glass.  The  achromatic  telescope 
has  been  of  the  utmost  importance  in  the  science  of 
astronomy.  Galileo,  DoUand,  D'Artigus,  Guinaud, 
Utzschn eider,  Bontemps  and  Ross  have  all  contri- 
buted to  accomplish  the  object ;  Frauenhofer  and 
Fresnel  have  carried  oft"  the  palm  in  the  solution 
of  these  great  problems.  The  telescope  and  micros- 
cope of  1869  are  proofs  of  what  has  been  done  in  this 
department  of  applied  science. 

The  artificial  gems  as  prepared  by  the  E-oyal 
Porcelain  Works  in  Berlin,  are  composed  of  a  frit 
of  6  dracliems  of  carbonate  of  soda,  2  drachems  burnt 
borax,  1  drachem  saltpetre  and  3  drachems  red  lead 
and  1^  ounces  fine  white  sand.  The  colors  to  be 
given  for  the  various  imitation  gems  are  as  follows: 

Sapphire  :  10  grains  carbonate  of  Cobalt ; 

Opal:  10  grains  oxide  of  Cobalt,  and 
15  "  manganese, 

30      "  iron. 

Amethyst'.  5  grains  carbonate  manganese. 

Gold  Topaz :  30  grains  oxide  of  uranicum. 

Emerald  :  20  grains  proloxide  iron,  and 
10     "    carbonate  of  copper. 

The  various  uses  of  glass. — When  we  consider  the 
many  uses  which  glass  is  applied,  its  cheapness,  its 


342 


SILICA,  OR  SAND. 


purity,  its  beauty,  we  find  that  it  possesses  tlie  valuable 
qualities  of  nearly  all  tlie  metals  ; — incorruptible  as 
gold,  clear  as  silver,  useful  as  iron,  what  would  our 
houses  be  without  it?  It  keeps  the  cold  out,  it  lets 
the  light  in.  We  drink  out  of  it,  and  we  see  our- 
selves in  it.  Besides  fulfilling  a  thousand  common 
and  domestic  uses,  it  is  made  into  gems  that  rival  rhe 
brilliancy  of  the  diamond,  and  into  lenses  which  give 
new  realms  to  human  vision.  It  restores  eyesight  to 
the  aged,  and  remedies  the  defective  eyesight  of  the 
young.  It  magnifies  objects  invisible  to  the  naked 
eye,  so  that  they  can  be  distinctly  seen  and  studied  ; 
and  it  brings  the  heavens  near.  To  it  we  owe  our 
intimate  acquaintance  with  the  stars.  The  telescope 
is  the  father  of  modern  astronomy,  and  the  soul  of 
the  telescope  is  glass. 

Colored  Glass. — With  few  exceptions,  the  oxides 
of  the  heavy  metals  possess  the  property  of  producing 
with  silica  colored  compounds,  which  may  be  com- 
bined with  ordinary  glass,  the  latter  being,  when 
pure,  a  colorless  compound  of  silica  with  oxides  of  the 
light  metals.  The  light  metals  are,  potassium,  iodine, 
calcium,  magnesium,  aluminium,  etc.  The  heavy 
metals  used  to  form  colored  compounds  are,  iron, 
copper,  cobalt,  antimony,  gold,  uranium,  manganese, 
chromium,  etc.  Lead  is  an  exception,  as  its  oxide 
forms  no  colored  compound  with  silica,  but  a  perfectly 


COLORED  GLASS. 


345 


transparent  and  colorless  one ;  in  fact,  it  transforms 
<iommon  glass  into  flint-glass.  There  are  two  methods- 
of  coloring  glass  ;  one  is  to  mix  the  metallic  oxide  in- 
timately with  the  material  of  common  glass,  or  of 
the  flint-glass,  and  put  both  together  into  the  pot ; 
this  kind  of  glass  is  therefore  called  pot-glass^  and  is 
only  used  for  the  colors  produced  bv  the  cheaper 
metallic  oxides.  The  second  method  produces  the  ^o- 
Q2\\q(\.  flashed  glass,  and  consists  in  covering  only  the 
surface  of  colorless  glass  with  a  very  thin  layer  of  the 
colored  glass.  This  may  be  accomplished  in  two 
ways.  By  having  two  pots,  one  with  colorless  and 
one  with  colored  glass,  and  dipping  a  globe  of  hot 
colorless  glass  into  the  pot  with  colored  glass,  a  layer 
of  the  latter  will  adhere,  and  by  the  dexterity  of  the 
workman  may  be  extended  over  the  whole  surface  of 
the  object  he  is  making,  be  it  a  goblet  or  a  window- 
pane.  The  other  way  is  by  means  of  a  brush  to  cover 
the  glass  object  after  it  is  made  with  a  cream-like 
mixture  containing  the  coloring  metallic  oxide. 
After  it  is  dry,  it  is  placed  in  a  suitable  furnace,  and 
heated  as  highly  as  the  glass  can  stand  without  melt- 
ing. It  is  then  slowly  cooled,  and  the  operation 
repeated  if  the  layer  applied  has  not  been  fused  sufti- 
ciently  to  combine  with  the  surface.  It  is  evident 
that  this  coloring  layer  must  be  slightly  more  fusible 
than  the  original  glass  object,  and  this  is  a  very  deli- 
cate point.    If  the  colored  mixture  be  too  fusible,  it 


COLORED  GLASS. 


will  melt  and  run  down  ;  if  not  fusible  enough,  the 
original  glass  itself  may  become  soft  before  this  com- 
bination has  taken  place. 

The  art  of  painting  on  glass  consists  chiefly  in  the 
preparation  of  the  diverse  metalic  oxides,  which,  by 
previous  tests,  are  known  to  produce  certain  colors. 
The  operation  is  rendered  peculiarly  difiicult  from 
the  fact  that,  at  the  time  the  colors  are  used  by  the 
artist,  they  all  look  nearly  alike,  being  a  dirty  brown. 
The  desired  colors  appear  only  after  the  pane  of 
glass  on  which  the  painting  has  been  made  is  exposed 
in  a  furnace  to  such  a  heat  as  to  melt  the  compound 
and  cause  it  to  combine,  to  a  greater  or  lesser  depth, 
with  the  surface  of  the  colorless  glass  beneath.  In 
olden  times  this  art  was  highly  esteemed,  as  is  evi- 
denced by  the  painted  windows  in  many  churches  on 
the  European  continent,  some  of  which  are  justly 
celebrated  as  containing  master-pieces  of  the  highest 
artistic  merit.  Among  them  stand  foremost  those  in 
the  Protestant  cathedral  in  the  city  of  Gonda,  Hol- 
land, a  Christian  Mecca  for  lovers  of  peculiar  art 
productions.  Among  the  common  people  of  Europe 
an  idea  prevails  that  some  secret  in  regard  to  this  art 
has  been  lost ;  this,  however,  is  by  no  means  the  case. 
The  manner  and  means  of  their  production  have 
always  been  perfectly  known  ;  but  we  no  longer  have 
the  artists  who  devoted  their  lives  to  the  practice  of 
this  very  difficult  and  hazardous  department  of  art. 


COLORED  GLASS. 


345 


In  this  kind  of  work,  as  in  the  preparation  of 
colored  glasses  in  general  the  effects  are  calculated 
for  transmitted  light,  the  colors  being  trunsparcnt. 
On  the  other  hand,  enameled  and  opaline  glasses  are 
intended  for  reflected  light,  and  in  such  cases,  opaque 
or  semi-translucent  glass  and  colors  are  used. 

In  general,  it  has  been  found  that  it  is  easier  to 
color  glass  when  it  contains  lead,  that  is  to  say,  flint- 
glass  ;  in  fact,  all  the  imitations  of  precious  stones, 
gems,  etc.,  are  made  from  a  very  soft  lead-glass,  its 
fusibility  and  aptitude  to  take  the  color  being  greater,, 
and  its  brilliancy  being  more  marked.  Soda  and 
lead  oxides  make  glass  more  brilliant  and  fusible,  but 
at  the  same  time  very  soft,  whence  the  name  of  paste, 
which  is  applied  to  this  compound,  such  imitation 
stones  being  in  reality  as  soft  as  a  paste  when  com- 
pared with  the  genuine  gems,  whose  hardness  is  so 
extreme  that  they  never  lose  their  polish  and  original 
lustre,  as  is  the  case  with  imitations.  For  this  reason, 
the  so-called  doublets  have  been  introduced,  in  which 
a  thin  genuine  gem  is  pasted  on  the  exterior  or  c  x- 
posed  surface  of  an  imitation  of  the  same  color  made 
of  soft  glass.  This  is  extensively  practiced  in  the 
East  Indies,  and  such  stones  will  of  course  retain 
their  polish,  but  can  never  be  fully  as  brilliant  as  the 
genuine  article. 

The  coloring  materials  for  glass  are  the  same  as  for 
the  imitation  gems,  only  in  glass  any  variety  of  color 


346 


COLORED  GLASS. 


may  be  used,  while  in  the  imitation  of  gems  we  can 
adopt  only  such  peculiar  colors  as  resemble  special 
gems. 

Yellow  glass. — This  is  produced  as  follows :  1st.  A 
dirty  yellow  by  charcoal,  passing  into  a  dark  brown 
if  the  coloring  agent  be  used  in  excess.  2d.  A  beau- 
tiful bright  yellow  by  antimony,  in  the  state  of  the 
so-called  glass  of  antimony,  or  antimonite  of  potash. 
3d.  Silver  in  combination  with  alumina,  in  the  state 
of  chloride  of  silver  and  clay.  4th.  Uranium,  in  the 
state  of  oxide,  produces  a  beautiful  but  expensive 
canary  yellow;  this  glass  is  very  interesting  to  the 
scientist,  as,  by  being  exposed  to  electricity  in  the 
dark,  it  becomes  illuminated  by  a  peculiar  greenish 
fluorescence. 

Hed  glass, — 1st.  Iron,  used  in  the  state  of  blood- 
stone or  ochre  as  derived  from  the  nitrate,  gives  a  cheap 
brownish-red  color,  whose  quality  depends  on  the 
purity  of  the  sesquioxide  of  iron  used ;  the  protoxide 
gives  another  color,  to  which  we  shall  refer  hereafter. 
2d.  Copper,  in  the  state  of  suboxide,  gives  a  very 
brilliant  red,  which  has  long  been  known.  A  pecu- 
liarily  is  that  this  glass  looks  nearly  colorless,  with  a 
slight  tinge  of  green,  when  leaving  the  furnace,  and 
only  becomes  red  when,  after  cooling,  it  is  heated  a 
second  time.  As  this  red  is  so  intense  as  to  make  the 
glass  opaque  if  not  used  in  very  small  quantity,  it  is 
always  flashed.    3d.  Gold,  in  the  form  of  purple  of 


COLORED  GLASS. 


347 


Cassius,  gives  a  scarlet,  carmine,  rose,  or  ruby  tint ; 
as  it  is  very  expensive  and  intense,  it  is  always  flasLed. 

Orange  glass  is  made  in  Bohemia,  from  a  glass  of 
antimony,  red  lead,  and  a  little  oxide  of  iron. 

Violet  glass. — Manganese,  in  tlie  state  of  peroxide ; 
care  is  to  be  taken  that  no  coal  or  soot  shall  come  in 
contact  with  it  during  the  melting,  as  the  carbon 
would  reduce  the  peroxide  to  a  protoxide,  which 
gives  no  color  at  all. 

Blue  glass, — Oxide  of  cobalt,  in  its  different  forms 
as  smalt,  zaffre,  etc.,  is  the  only  true  blue  color  pro- 
duced in  glass ;  the  shade  and  tone  is  modified  by 
different  quantities  and  admixtures. 

Green  glass. — 1st.  Protoxide  of  iron,  in  small 
quantity  ;  the  resulting  glass  has  little  brilliancy.  2d. 
Peroxide  of  copper  gives  a  beautiful  emerald  green  ; 
if  the  glass  contains  lead,  it  is  more  brilliant  still ;  if 
the  glass  is  not  transparent,  but  dull  or  only  translu- 
cent, it  becomes  deep  blue.  3d.  Chromium,  in  the 
state  of  the  sesquioxide,  or  genuine  pure  chrome 
green,  gives  a  brilliant  grass-green  color.  It  bears  a 
high  price.  4th.  A  mixture  of  the  oxides  of  nickel 
and  uranium ;  this  is  used  in  Bohemia,  where  the 
color  produced  is  called  modern  emerald-green,  to 
distinguish  it  from  the  peroxide  of  copper  green, 
which  they  call  ancient  emerald-green. 

Blade  glass. — A  mixture  of  forge-scales,  (protoxide 
of  iron,)  bone-ashes,  (phosphate  of  lime,)  and  char- 


COLORED  GLASS. 


coal,  (carbon,)  in  excess,  added  to  ordinary  materials, 
makes  a  black  glass,  which  in  Bohemia  is  called 
jasper;  it  is  perfectly  opaque,  very  hard,  and  pos- 
sesses a  remarkable  lustre.  Its  properties  are  such 
that  it  may  be  used  for  boiling  liquids  without  risk 
of  breakage.  It  is  reported  that  in  Bohemia  basalt 
or  lava  is  used,  with  or  without  the  forge-scales. 

Bronze  colored  glass. — If,  in  the  last  recipe,  lead 
slags  are  substituted  for  the  forge-scales,  an  opaque 
yellowish  bronze-colored  jasper  is  produced.  Bottles 
of  the  opaque  blackish  kinds  of  glass  are  now  exten- 
sively used  by  chemists  and  photographers,  to  protect 
many  chemicals  that  are  sensitive  to  light  against  its 
decomposing  influence.  These  bottles  are  mostly 
imported  from  Bohemia. 


I  ISTD  EX. 


Absorption  of  Bricks,   209 

Account  of  Boerhave,   19 

Acid:  Hydrofluoric,  57,  181,  2<18; 

Perchloric,  181  ;    Phenic,  173 ; 

Phosphuric,  138;  Sulpliuric,  133. 
Advantutros  of  Concrete  Pavement 

over  Stone  or  Wood,  1S7;  over 

Iron  Block  Poveinent,  200. 

Aerolites,   21 

Agate,  29;  Banded,  29;  Colored, 

29;  Jasper,  31;  Moss,  29;  Opal,  36 

Age  of  Formations,   308 

Aggregate  of  Geological  Epochs 

form  an  Infiniteeimal  Portion  of 

Eternity,   275 

Albumen 'of  the  Sap,   153 

Alcohol  Barrels,  Protection  of  210 

Alkali,  44;  Origin  of   309 

Alkaline  Silicates,  13,  94,128;  Con- 
tact of,   213 

Alluvial  Sand,  87;  Sandstone,  37, 

Alum,   145 

Alumina,  an  Excellent  Flux  for 

Lime,  (57,  72 

Alumiiiate  of  I.iinc.  Hydration  of, 

67,  6->;  Absorbs  Phos^phorus,  68; 

Absorbs  Suli)hur,  68. 
Aluminates  of  Lime,  Hydration  of, 

67;  and  Calcareous  Clay,  71. 

Alumocalcite,   37 

American    Limestone  Hydraulic 

Mortar,   87 

Ametiiystine  Quartz,   26 

Ammonia,   173 

Analcime,    39 

Analysis  of  Portland  Cement,  73; 

Rondout  Hydraulic  Lime,  T5 ;  of 

Sap,  164. 

Ancient  Ceiiiont,  96;  Law  for  Lime, 

98;  Law  for  Sand,  98;  Mortar 

Hardnes.s,  95. 

Angular  Grains  for  Mortar,    84 

Anhydrous  Silicates,   39 

Animal  and  Vegetable  Albumen, 

153;  Acts  like  a  Ferment,  153. 

Anti-Kust  Paint,    53 

Apophyllitc   12S 

Aqu.irium  Cement,   218 

Argillaceous  Limestone,  68;  Strata, 

104;  Sandstone,  37. 

Arkansas  Hot  Springs,   292 

Arrangement  of  Kocks,  305 

Arsenic,  White,    40 


Artificial  Gems,  341 ;  H3'draulic  Ce- 
ment, 94. 
Artificial  Stone,  58;  Author's,  56; 
Explanation  of,  123 ;  Ransome's, 
54;  Silicilication  of,  128;  To  Ex- 
cel Nature,  58. 
Artificial  Sulidiate  of  Barvta,  138; 
Its  Proportion,  138. 

Asbestos  Cement,    53 

Ash  and  Oak,  Decrease  in  Weight,  148 
Asphalt  :     Compound    for  Wall 
Damp,  82;  Pavement,  179;  Cost 
of.  1^1;   Utterly  Impervious  to 
Water,  181. 

Athens  Marble  Cement,   223 

Atolis  formed  by  Fringe  Reefs,   285 

Authors  Artificial  Stone,  56;  Pre- 
paration, 142;  Process,  142. 

Aventurine   27 

Babel  Quartz,   34 

Banded  Agate,   29 

Bariila,   19 

Barium,  Chloride  of,  138 

Barrel  l.ining,   52 

Barvtn,  138;  A  Fine  Paint,  87;  En- 
amel, 138;  Paint,  133. 
Basic  Efl'ects  of  Carbonate  of  Lime,  114 

Belgian  Pavement   178 

Berlin  Museum  Painted  by  Kaul- 

back,   128 

Berzelin's  Cement,  78;  Discovery,  21 
Beton  Building,  228;  Process  of,  229 
Beton  Coignet  Concrete,  182 ;  Great 
Durability,  182;  Its  Cost,  182. 

Bisilicatcs,   89 

Bittern  of  Salines,   51 

Blanc  Fix,  189;  Its  Manufacture, 
139;  Mixed  with  Starch  andDex- 
terine,  139;  Not  Dilitorv  upon 
Health,  139. 

Bloodstone  Cement,   133 

Boerhave's  Account,   19 

Bohemfan  Glass,   13 

Bone  Dust   142 

Bookbinders'  Pa3te,a  Substitute  for,  221 

Borax   145 

Bottle  Glass,   18 

Boucherie's  Process,   145 

Bouilly's  Cement,   79,  105 

Bracannot's  Ink,   183 

Brewery  Cement,  ...    214 

Bricks,  Absorption  of,  209 ;  of 
Roman  Walls,  62. 


15 


350 


INDEX. 


Bridges  of  Concrete,   216 

Broadway  Pavement,   196 

Brooklyn  Navy  Yard,   15,  141 

Brown  and  Miller  Pavement,  204; 
Similar  to  Nicolson,  204. 

Buhrstone,   33 

Building. Marerial,  49;  Timber  Se- 
cured, 142 ;  Wooden,  127. 

Burnett's  Process,   145 

Cachelong,   35 

Cadmium,  aulphuret,  126 ;  Yellow,  138 
Calcareous  Clay  and  Aluininate  of 
Lime,  71 ;  Deposits  in  Thermal 
Springs,  291 ;  Rocks  Divided  into 
Uncrystalline  and  Crystalline, 
290 ;  Ten  Varieties,  290. 
Calcium  is  one  of  the  Nine  Elements 
and  Forms  997-1000  of  the  Earth's 

Crust,   277 

Calcination  of  Earth,  43;  Flint,  38; 

Hornstonc,  38 ;  Quartz,  33;  Sand,  48 
Cannel  Coal  Tar  contains  7  per  ct. 

PhenicAcid,   174 

Cannon  Balls  Preserved,    16 

Cap  Quartz   26 

Captain  Kotzebue's  Description  of 

Coral  Islands,   280 

Carbon,  240;  Character  of,  249. 
Carbonate  of  Lime,  Basic  Elfect«  of, 

114;  Silico,  16;  Soda,  314. 
Carbonic  Acid  Essay,  236 ;  Gas, 
140 ;  Produced  in  Quantity  of,  . .  251 

Carlsbad  and  Selzer  Springs,   253 

Carnelian,   29 

Cat's  Eye  Quartz,   27 

Cause  of  Hardening,   115 

Cause  of  Damp  Walls,   85 

Caustic  Lye,   20 

Cavernous  Quartz,   26 

Cellar  Cement,   53,  76 

Cement  against  Steam,  224;  An- 
cient, 96;  Aquarium,  213;  Asbes- 
tos, 53;  Athens  Marble,  223; 
Berzelin's,  78;  Bloodstone,  133; 
Bouilly's,  79, 105;  Brewery,  214; 
Cellar,  53;  Cistern,  77,  226;  Clay, 
225;  Drain  and  Gas  Pipe,  225; 
Emery,  133;  Fire,  76 ;  Fire  Brick, 
53 ;  Fire  Proof,  223 ;  For  any  Sub- 
stance, 78;  For  Dry  Walls  and 
Cellars,  76;  For  Glass  and  Metals, 
222 ;  For  Iron  and  Stone,  71 ;  For 
Metals,  222;  Foundation  Wall, 
224;  Glass,  78;  Gypsum,  225; 
Hamelin's,  78;  Hamilton's,  105; 
Hard,  134;  Hard  Adhesive,  225 ; 
Impermeable,  224 :  Iron,  77,  226 ; 
Keene's,  66;  Kuhlman's,  78; 
Lute's,  77;  Malt  House,  214; 
Manganese,  183;  Martins,  66; 
Meaning  of,  73;  Metallic,  224; 
Most  Adhesive  Insoluble,  212; 
Most  Refractory,  227;  Parian, 
66;  Peasley,  116;  Plaster,  66; 
Portland,  65;  Reese's,  78,  105; 
Roman,  65,  104;  Roofing,  53; 


Solidifying  Property,  102 ;  Sort I's, 
108 ;  Steam  Resisting,  77 ;  Stinde's, 
96;  Stone.  74;  Stove,  226;  Strong 
Iron,  116;  Terra  Cotta,  79,  105; 
Various,  222 ;  Water  Tanks,  214 ; 
with  Chloride  Calcium,  49 ;  Zinc,  224 

Chabasite,   39 

Chalcedony  Quartz,   28 

Chalk,  a  Substitute  for  Lime,  57; 
Flints  in,  20;  Flints  of,  32  :  Hard- 
ening of,  17;  origin  of,  296;  Silici- 
fication.  58. 
Characteristic  Features  of  Chalk, . .  323 

Character  of  (Carbon   249 

Character  of  Glass,   336 

Character  of  Potassium,    310 

Charcoal  Application,   41 

Charring.  Not  Consuming,   141 

Cheap  White  Paint,   126 

Cheapest  Lubricator,  212;  White- 
wash, 913;  Yellow-wash,  213. 

Chert,    32 

Chloride  Calcium,   17,  48 

Chloride  of  Barium,   138 

Chloride  of  Lime,  140 ;  of  Iron,  48. 

Chimes  of  Barrels  Filled,   250 

Chrome  Red,   138 

Chrysoprasc,   29 

Circular  of  Uses,   50 

Cistern  Cement,   77,  226 

Cisterns,  Protection  of,   210 

Classification  of  Glass,  .331,  333;  of 
Rocks  of  New  York  City,  by 
Dr.  Stevens,  303. 
Clay  Cement,  225;  Clay  and  Chalk,  142 
Clay,  Per  Centageof,  102;  Siliceous, 
75;  test,  38. 

Cleavage  Quartz,   23 

Coal  Tar  Recommended,   143 

Coating  of  Stone,   207 

Cobalt  Blue   138 

Cochineal  Ink,   133 

Cold  Water  poured  over  the  Mass, .  42 
Colored  Agate,  29 ;  Jelly.  43. 

Colors  of  Quartz   24 

Colors  Syringed  on  Painting,   135 

Combustion,  Protection  against,...  140 

Coming  Pavement,   185 

Commodore  Perry,   16 

Common  Opal,  35;  Sandstone,  37. 

Composition  of  Doebereiner,   15 

Composition  with  Silicates,   106 

Compounds  of  Oxygen,  38;  of  So- 
dium. 813. 

Compound  Water  Glass,   16 

Concrete,  66 ;  Beton  Coignet,  182 ; 
Fiske,  200 ;  for  Bridges,  216  ;  for 
Floors,  216 ;  for  Wall  Damp,  81 ; 
Pavement,  179. 

Condensation  of  Silica,   119 

Conglomerate  Quartz,   33 

Concretionary  Quartz,   24 

Consolidation  of  Shells  and  Corals 
by  the  Precipitation  of  Calcareous 
and  Ferrugenous  Matter,  279; 
Florida  Keys  an  Example,  280. 


INDEX. 


351 


Constituents   of  Glass,   329 ;  of 
Quartz,  22,  26. 

Conversion  of  Silicate  of  Lime,   134 

Copperas,  Solution  of,   144 

Copper  Scales  Additional,   43 

Copper,  Sulphate,   145 

Corals  Covered  with  Expanded 
Polyps,  284  :  Kcseuiblinp  Forms 
and  Colors  of  P'iowt-rs,  284 ;  Waves 
Destructive  to,  284. 
Coral  Formations,  Thickness  of, 
285;  Certain  TroDical  (Coasts  Ex- 
empt. 282 ;  Tropics  the  Hot  Beds 
for,  282. 

Coral  Islands  Described  by  Captain 
Kotzebue,    280;    in    the  Pa- 
cific, 282,  290. 
Coral  Plantation  with  Bare  Patches,  281 

Coral  Platform,   283 

Coral  Koef  Building  as  Described  by 
Hirsch,  286:  One  Hundred  and 
Twenty  Species,  286. 
Coral  Keef,  Two  Thousand  Feet 
Thick,  2*^2;      Corresponds  to 
190,000  years,  282. 
Coral  Reef  Kock,  Consolidation  of 
Fragments  Form,  285;  Frins;ing 
or  Barrier  Reefs  Formed,  285. 
Coral  Kocks  Cover  Millions  of  Acres, 
280;  Descends  in  Perpendicular 
Columns,  280;  Divided  into  Five 
Kinds,  283. 

Cost  of  Asph.alt  Pavement,   181 

Cost  of  Boton  Coignet  Concrete,  . .  182 

Crab  Grass,   19 

Cretaceous  Belt,  105;  Period,  299. 
Cross-Ties,  51    Protection  of,  210. 

Crypto-Crystalline  Quartz,   25 

Crystal  ¥(nm  Quartz,   23 

Crystal  Glass   13 

Culinarv  Vessels,  Euanielling  of,  ..  222 
CvpressStem  with  3.000  Kings,  163: 

of  3,000  years,  163. 
Damp  Wall  Application,  85 ;  Causes 
of,  85;  Clay  and  Whiting  for,  86; 
Lime  and  Portland  Cement,  86. 
Dead  Oil,  146;   Absorbs  Oxygen, 
146;  Coagulates  Albumen,  146; 
Complete  Protection,  148;  C'on- 
tains  Carbolic  Acid,  147;  Protects 
against  Damp  and  Wet,  146;  Pro- 
tects  from   Cremacausis,    146 ; 
Protects    from    Parasites.  140; 
Poisonous  to  Animal  and  Vege- 
table Life,  146;  Shuts  out  Air 
and  Moisture,  146. 
Decrease  in  Weight  of  Ash  and  Oak,  148 
Dentists   use    Silica    fts  Plaster 

Moulds   52 

Dentritic  Forms,   31 

Dentrition  at  Falls  of  Niagara,   258 

Deposits  of  Salt,  313 ;  How  Obtuined, 

318;  Its  Usep,  313. 
Descrii)tion  of  Green  Sand,  818;  of 
Quartz,  316;  of  Sand,  816;  of 
•    Sand  Stone,  315. 


Different  Kinds  of  Polypiferous 
Zoophytes,    2S0 

Disappointment  and  Duff's  Groupes 
Visit  each  other,   280 

Discoverj'of  Berzelins,   21 

Disintegration,  38;  ot  Granite,  256; 
of  Stone,  55. 

Dissolved  Quartz,  34;  The  Gey- 
sers, 34. 

Distillation,  Process  of,   173 

Distincticn  of  Animals  and  Plants,  261 

Division  of  Rocky  Masses,   305 

Doebereiner's  Composition,   15 

Dolomite  and  Silicate,  90;  Compo- 
sition. 90;  Forms  Extraordinary 
Hard  Stone,  71. 

Double  Soluble  Glass,   44 

Drain  and  Gas  Pipe  Cement,   225 

Dr.  KricL'   175 

Dr.  Loew's  Remarks,   264 

Dr.  Liebig's  Remarks,   265 

Dr.  Stevens' Classification  of  Rocks,  308 

Dr.  T.  Sterry  Hunt's  Remarks,  268 

Drusy  Quartz,   26 

Drying  of  Timber,  170 ;  by  Steana,  148 

Dry  W^ all  Cement,   76 

Dunging  Salt   15 

Dust,  Volcanic   99 

Earth,  Calcination  of,  43;  History 
of,  275;   Infusorial,  20:  Must 
have  had  a  Beginning.  275. 
Easel  Painting,  Stereo-Chromic,  ..  137 

Effloresence  of  Alkali,   44 

Egyptian  Jasper,   33 

Emery  Cement,  ...    183 

Eminently  livdraulic  Lime,   64 

Enamel,  Barvta,  133;  Oxide  of 
Chrome,  133;  I'ltramarine,  133. 

Enamelling  Culin.ary  Vessels,   222 

Essay  on  Carbonic  Acids,  236;  on 
Lime  Stones,  273. 

Evaporation  to  Consistency,   42 

Evidence  of  the  Beginning  or  End 

of  the  Globe   276 

Examination  after  One  Year's  Ex- 
posure,   136 

Experiments  of  Ilansome,  17;  of 

Rumford,  169  ;  with  Square  Blocks,  141 
Explanation  of  the  True  Artificial 

Stone,   123 

Exjjosure  for  Ten  Days,  44 ;  to  Pres- 
sure, 20,  57. 

Extraction  of  Soluble  Salts,   55 

Farm  Houses   149 

Felspar,  37,  92;  Lime,  39;  Mica, 
39 ;  Soda,  39  ;  Potash,  39. 

Ferruginous  Quartz,   27 

Fibrous  Quartz,   26 

Fire  Brick,  223;  Cement,  53. 

Fire  Cement,   77 

Fire  Opal   36 

Fire  Proof  Cement,  223;  Paint,  62, 

Fiske  Concrete   .  200 

Flint,  31 ;  Calcinntion  of,  88;  Glass, 
18;  in  Chalk,  20;  ol  Chalk,  32; 
Marble,  87. 


352 


INDEX. 


Floors  of  Concrete,   216 

Florida  Keys,   280 

Florite,   36 

Fluohydric  Acid  for  Hardening, ...  40 
Fluorcalcium  and  t>oluble  Glass, .  . .  132 
Fluoride  Calcium,  a  Fusible  Silicate,  40 

Fluosilieate  of  Lime,   131 

Fl  or  spar,   40 

Formation  of  Opal,  119;  of  Quartz, 

119;  of  Saltpetre,  119. 
Formations,  Ape  of,  308;  Under 
the  Surface  of  the  Sea,  from  De- 
positions or  Chemical  Precipita- 
tion,   278 

Foundation  and  Upper  Pan   195 

Foundation  Wall  Cement,   244 

Fracture  Quartz,   24 

Frame  Houses,  Protection  of,   210 

Freestone,   317 

Frequent  KenewalsExi)ensive,   194 

Fresco  Painting,  117;  Its  Silicifica- 

tion,  117;  Substitute,  127. 
Fringing  or  Barrier  Coral  Eeefs,. .  .  285 

Fringe  Eeefs  from  Atolls,   285 

Frog  Grass,    19 

Fungi  Require  Oxygen  for  Genera- 
tion  166 

Furnace,  Rcverberatory,   41 

Fusing  Quartz,   22 

Gas,  Carbonic  Acid,  140;  Oxygen,  140 

Gems,  Artificial,  341 

German  Hydraulic  Cement,   94 

Geodes  Quartz,   34 

Glass,  328;  Bohemian,  13;  Bottle, 
13;  Cement,  78;  Character  of, 
336;  Classification  of,  331,  333; 
Constituents  of,  329;  Crystal, 
13;  Double  Soluble,  44;  Flint, 
13;  Frog,  19;  History  of,  328; 
Manufacture  of,  335;  Metal  Ce- 
ment, 222 ;  iSlot  Scratched  by 
Steel.  44;  Physical  Character  of, 
S34 ;  Soluble,  13,  39,  141  ;  Stross, 
13 ;  Varieties  of,  339  ;  Water, 
13;  Window,  13. 

Glauber  Salts  40,  138 

Globe,  Solid  Surface  of,   21 

Glue,  a  Substitute  for,   221 

Granite,  !  >isintegration  of.   256 

Granite,   Gneiss,   Micaschist  and 

Compact  Limestone   304 

Granite  Pavements,  198;  Become 

Polished  and  Slipperj',   199 

Granitic  Sand,   37 

Granular  Quartz   33 

Grape  Vines,    Soluble   Glass  as 

Manure  for   919 

Gravel,   37 

Great  Colorado  Gors'e,  2'"0 

Green  Sand,  105,  816;  Composition,  105 
Green  Vitriol,  impregnated  with 

Silica,   127 

Grotto  del  Cane,   253 

Gvpsum  <\'ment.  225;  Silicification 

of,  114 ;  and  Lime,  115. 
Hameliu's  Cement   78 


Hamilton's  Cement   105 

Hard  Adhesive  <  ement,  225 

Hard  Cement,  133;  Mortar  Formed,  137 
Hatdening  of  Chalk,  17;  of  Lime 

Similar  to  Gypsum,   122 

Hardening  Process,   92 

Hardness  of  Ancient  Mortar,  95; 
of  Quartz,  24. 

Hard  Limestone,   62 

Haytorite,   33 

Heart  Wood  Resists  Kot,   146 

Heliotrope,    29 

Herb  Kali,   19 

Herkimer  Quartz,   24 

Heulandite,   39 

History  of  Glass,  328;  of  the  Earth,  275 
Hornstone,  32;  Calcination  of,  38. 

Horses,  Loss  of,   193 

Hot  Springs  of  Arkansas,   292 

Houses  of  Parliament,   18 

House  Timber.   51 

How  to  Coat  Wood,  141 

Ilyahte,    38 

Hydrated  Silico  Carbonate,  114 

Hydrate  of  Lime,  Reaction  of,   68 

Hydration  of  Aluminates  of  Lime,  G7,  68 
Hydraulic  Cement,  Artificial,  94  ; 

Composition,  94;  German,  94. 
Hydraulic  Lime,  58,  64;  Infei-iority, 
102:  Meaning  of,  65;  Mortar, 
58,  90;  Where  Found,  91. 
Hydraulic   Limestone,  American 

Mortar   90 

Hydraulic  Pre' sure,   48 

Hydraulicity  of  Magnesia,    69 

Hydiocarbons  Solid  at  400  to  500 

deg.  F.,   174 

Hydrochlorate  Amnionia,   130 

Hydrofluoric  Acid,  131,  208;  Appli- 
cations, 208;  Forms  an  Insolu- 
ble Compound,  131 ;  Mixed  with 
Gypsum,  132;  Price  of,  57. 

Hydrogenium,   238 

Hydrophane,   35 

Hydrous  Silicates,   39 

Imitation  Sandstone,   57 

Impermeable  "    224 

Impregnation  of  Wood  by  Pres- 
sure. 156 ;  by  Preservative 
Liquids,  157. 

Increase  in  Weight,   144 

Indeetructible  Ink,  133 

Indurating  Action,   54 

Inferiority  of  Hydraulic  Lime,  .  .  102 
Infusorial  Earth,  20;  Instead  of 
Sand,  43. 

Infusoria  of  Planitz,   20 

Injection  of  Silicates   118 

Ink,  Braconnot's,  133;  Cochineal, 
133;  Indestructible,  133. 

Insoluble  Precij)itate  of  Silica   144 

Iron  Block  Pavement,  199 ;  Fails  in 
New  York,  199;  Its  Advantages, 
200;  Succeeds  in  Boston,  199, 

Iron  Cement,    77,  22fl 

Iron,  Chloride  of,   48 


INDEX. 


353 


Iron  and  Stone  Cement,   77 

Iron,  Oxide  of,  138;  Pyrolignite  of,  145 
Iron  Ship  Bottoms,  Preservatives  of,  212 

Iron  Test,   38 

Itacolumite,   33 

Jasper,  29;  Agate,  31;  Porcelain, 

33 ;  Egyptian,  33. 
Jelly,  Colored,  43;  Liquid,  16  ;  Silica,  20 

Juice  in  Vascular  Tissue,   164 

Kali  Herb,  19;  Vitrifying,  19, 

Kaulbach's  Soluble  (Jlass,   44 

Keene's  Cement   66 

Kelp   19 

Kreosotc  Carbolic  Acid,   143 

Krieg'&  Recommendation  in  1858,,  143 

Knhlman   16 

Kuhlmaii's  Cement,  78 ;  Theoretical 
View,  112. 

Kunkcl   19 

Kyan's  Process,   145 

Laths,  Protection  of,   210 

Launionitc,    122 

Lavoisier  on  the  Cause  of  Harden- 
ing,   98 

Left- Handed  Crystal  Quartz,   25 

Liebig,  16 ;  Process  of,  20, 
Light  Oil,   173 


Lime,  Ancient  L,iw  for,  90;  Animal 
Product,  274;  Chloride  of,  140; 
Combination  with  Phosphoric 
Acid,  276;  Derived  from  Disin- 
tegrated Kocks,  274;  Eminently 
Hydraulic,  64;  Felspar,  39;  Fhio- 
siiicated,  131 ;  Hydraulic,  68,64; 
Made  through  the  Agency  of 
Life,  Animal  or  Vegetable,'276 ; 
Medium  of  Organic  Beings  in  the 
Inorganic  Process,  276;  Mode- 
ratelv  Hydraulic,  64 ;  Plastic, 
112;"Poor,  64;  Rich,  61,64;  Se- 
creted by  Testacia  and  Corals, 
274;  Speculation  on  the  Origin  of, 
277;  Silicate,  15,  18;  Test,  38; 
Water,  100;  Weight  of,  74. 

Limestone,  273;  Argillaceous,  68; 
Hard,  63;  Magnesian,  18,  52;  of 
New  York  Island,  301;  Described 


by    Cozzens,    302 ;  Silicifica- 
tion  of,  131. 

Limped  Quartz,   26 

Lining  for  Barrels,   52 

Linseed  Oil  Barrels,  Protection  of,  210 

Liquid  Jelly,    16 

Lithograj)hic  Stones,   187 

Locust  and  Cedar  Resist  Decom- 
position,   154 

Long  Leafed  and  Northern  Pine,..  167 

Loss  of  Horses,   193 

Lubrkator,  Cheapest,   212 

Ludus  Helmontii,   75 

Lustre  of  Quartz,   24 

Lute's  Cement,   77 

Lydian  Stone,   32 

Lye,  Caiistic,  20;  Preparation  of,..  43 
Lyeirs  Arguments,  278;  Subdivi- 
sion of  Kocks,  308. 


Mac  Adam's  Pavement,  1 80 ;  System 

in  1816,  184. 
Magnesia,  Hydraulicity  of,  69;  in 

Mortar,  93. 
Magnesian  Limestone,  18,  52 ;  of 

Potsdam  Period,  293, 

Magnesium,  Oxychloride  of,  51,  108 

Malt  House  Cement,   214 

Mamillary  Quartz,   24 

Manganese  Cement,  133 ;  Peroxide,  126 
Marble  Cracks  and  Crevices,  52; 

Flint,  87. 

Marly  Sandstone,    37 

Martin's  Cement,   66 

Manufacture  of  Glass,   335 

Materials  for  Building,  49;  Formed 
into  Rocks,  269, 

McGoncgal  Pavement,   202 

Meaning  of  Hydraulic  Lime,  64;  of 
Cement,  73, 

Menilite,   36 

Merits  of  Wooden  Pavements,  1S8 

Mesotvpe,   122 

MetalCement,    222 

Metalic    "    224 

Method  of  Preserving  Wood,  155; 
By  Cold  and  Tepid  Water, 
155;    Withdrawing  the  Albu- 


men, 155. 

Method  of  Vicat,   103 

Mica  Composition,  39 ;  Felspar,  39, 

Micaceous  Sandstone,   37 

Microscopical  Parasites,   162 

Milky  Quartz,   27 

Millstones,   49 

Mississip])i  River  Sand   37 

Mixture,  Vicat's,   103 

Mocha  Stone   31 

Mode  of  Application,   207 

Moderatel}' Hydraulic  Lime,   64 

Monuments,  49;  Restored,  123. 
Mortar  between  Bricks,  62:  Hy- 
draulic, 38,  90  ;  Magnesia  in,  93; 
Receipts,  80:  Roman,  96;  Rough, 
128:  Silica  in,  93. 

Moss  Agate,   29 

Most  Adhesive  Insoluble  Cement, .  212 

Most  Refractory  Cement,  227 

Mucilage,  A  Substitute  for,  22l 

Munich  Theatre,  16,  129, 141 ;  Solu- 
ble Glass  used  in,  129. 
Mushroom  Attacks  Wood,   166 


Natural  Silicates,  119, 122:  Apophvl- 
lite,  122;  Effloresence,  122;  Lau- 
monite,    122;    Mesotype,  122; 


Stilbite,  122. 

Nature  of  Lime  Determined,   63 

Nature  of  Traffic,   195 

Navy  Tard,  Brooklyn,   15,  141 

Neri's  Treatise   19 

New  Castle  Coal  contains  2>^  per 

cent,  Phenic  Acid,   174 

New  Jersey  River  Sand,   3*? 

Niagara  Falls  Detrition,  258 

Nicolson  Pavement,   201 

Nineteenth  Century,   5S 


354 


INDEX. 


Nitrate  Soda,  40,  121;  Where  De- 
rived, 121 ;  Where  Found,  121. 

Non-Intiammable  Wood,   51 

NuUipores,  Calcareous  Vegetation,  284 

Nullipores  Look  Like  Plants,   2S8 

Oak  and  Ash  Decrease  in  Weight,.  148 
Objections   to    Stone  and  Wood 

Pavements,    188 

Oertlyand  Fendrich,  107;  Coating, 
107;  Iron  Stone,  lUS;  Kadiating 
Power.  110;  Eemarks,  110. 
Oil,  Brownish,  173;  Light,  173. 

Oleaginous  Va])or  Process,   172 

Onyx   31 

Opal,  35:  Agate,  36;  Common,  35; 
Fire,  35  :  Formation,  119  ;  Green, 
35;  (h-ange,  35;  Kesin,85;  Solu- 
ble in  Potash,  37;  Wood,  36. 

Orange  Opal   35 

Ordnance  Department,   15 

Origin  of  Alkalies,  309;  Calcareous 

Deposits,  291  ;  Chalk,  296  ;  Lime,  277 
Oxide,  Burnt,  138  ;  Chrome,  126  ; 
Chrome  P^namel,  133  ;  iron,  138  ; 
Eaw,  138. 

Oxychloride  of  Magnesium,  51,  103 

Oxygen  Compounds,  38  ;  Gas,  140. 
Pacific,  290  ;  Coral  Islands  in  the,  282 
Paint,  An ti -Rust,  53  ;  Baryta,  133  ; 

Fire-Proof,  52. 
Painting,  Exposed  for  One  Year, 
128:  Fresco,  117;  Silica,  132: 
Silicate,  117  ;  Precaution  in,  135  ; 
Upper  Ground  for,  137 ;  with 
Brush,  208. 

Parian  Cement,   66 

Parisian  Pavement,   179 

Patents  of  Bobbins  and  Moll,   175 

Pavement,  Asphalt,  1T9  ;  Broadway, 
196;  Brown  and  Miller,  204; 
Granite,  198 ;  Granite  becomes 
Polished  and  Slipperj^  199  ;  Iron 
Block,  199  ;  Iron  Blocks  Fail  in 
New  York  and  Succeed  in  Bos- 
ton, 199  ;  McGonegal.  202  ;  Nicol- 
son,  201  ;  Bobbins,  204;  Seeley's 
(Concrete,  205:  Stafford,  204; 
Stowe,  203;  The  Coming,  205; 
Typical  Historical,  191. 
Payen  Recommends  Caustic  Alkali,  154 

Pearlash,  Purifying  of,   39 

Peasley  Cement,   116 

Percentage  of  Clay,   102 

Perchloric  Acid,   131 

Permanent  White,   138 

Phenic  Acid,  173  ;  Cannel  Coal  Tar 
Contains  7  per  ct.,  Newcastle  2)4 
per  ct.,  Staffordshire  4>^  per  ct., 

Average  5  per  ct.,   174 

Phenocrystalline  Quartz,   25 

Phenomena  of  Good  Lime,   63 

Phosphoric  Acid,   138 

Physical  Character  of  Glass,  334 

Pitch  of  Dead  Oil,   146 

Planitz,  Infusoria,   20 

Planks  and  Blocks,  How  to  Prepare,  206 


Plasma,    29 

Plaster  Cement,  66  ;  Paris,  66. 

Plastic  Lime,   112 

Pliny  and  Vitruvius,   97 

Pliny's  Ideas  on  Wood  Decay,  166  : 
Statement,  19. 

Polarization  of  Quartz,   24 

Poles,  Telegraph,   51 

Polveriue,   19 

Polypifurous  Zoojihytes   280 

Pontine  Marshes,   74 

Poor  Lime,    . .  64 

Porcelain  Jasper,   33 

Portland  Cement,  05  :  Analysis,  73  ; 

Where  Manufactured,  104. 
Potash  Felspar,  39  ;  Silicate,  13 : 
Soluble  Glass,  41  ;  Soluble  Glass 
Whitewash,  44  ;  Water  Glass,  18. 
Potassium,  21  ;  Character  of,  310  ; 
Compounds,  311  ;  Fluoride,  21 ; 
Siliciuret,  21, 

Prase,    29 

Precaution  in  Painting,   135 

Precipitated  by  Alcohol,   42 

Preparation  of  Planks  and  Blocks,.  206 

Preparing  Underground,   130 

Preservation  by  Champty  (Dipping 
in  Suet),  152  ,  by  De  Saussure, 
152,  by  Fagol  (1T40),  bv  Haller 
(1756j,  bv  Jackson  (1767),  by 
Kyau  (1830),  by  Pallas  (1779), 
151 ;  by  I'ayeu  {Dipping  in 
liosin),  152  ;  by  Immersion,  150  ; 
of  Walls,  209  ;  with  Alum  and 
Sulphate  of  Iron,  151. 
Preservatives  of  Iron  Ship  Bottoms,  212 

Price  of  Hydrofluoric  Acid,   57 

Process  01  "Distillation,   173 

Process  of  LiebiK,  20  ;  of  Violitter,  148 
Prof.  Henry's  Statement  of  Niagara 

Falls,   259 

Prosser's  System,  162 

Protection  against  Combustion, 
146  :  of  Alcohol  Barrels,  Cisterns, 
Cross  Ties,  Frame  Houses,  Lath, 
Linseed  Oil  Barrels,  Rail  Road 
Sleepers,  Staves.  Shingles,  Spirits 
Turpentine   Barrels,  Telegraph 

Poles.  Timber,   210 

Prismatic  Face  Quartz,   24 

Pseudomorphous   "    83 

Pumice,  Volcanic,   99 

Pure  Silica,   38 

Purifying  Pearlash,  39 ;  Soda-ash,  39 

Puzzuolana,   61 

Puzzuolanic  Action,  67  ;  Silicates,..  69 

Pyrolignite  of  Iron,   145 

Quantity  of  Carbonic  Acid  Pro- 
duced,   251 

Quartz,  Amethystine,  26 ;  Aven- 
turine,  27  ;  Babel,  34  ;  Calcination 
of,  38  ;  Cap,  26  ;  Cat's  Eye,  27 ; 
Cavernous.  26  ;  Chalcedony,  28  ; 
Characteristic  Features  of,  323  ; 
Cleavage,  23;  Colors,  24;  Con- 
nectionary,  24 ;  Conglomerate, 


INDEX. 


355 


33  ;  Constituents  of,  22, 25  :  Cryp- 
to-Crystalline,  25  ;  Crystal  Form, 
23;  Description  of,  316;  Dis- 
solved, 34  ;  Drnsy,  26  ;  Ferrugin- 
ous, 27  ;  Fibrous,  26  ;  Formation, 
119;  Fracture,  24;  from  Herki- 
mer, 24  ;  from  Ulster,  24  ;  Fusing-, 
22  ;  Geodes,  34  ;  Granular,  33  ; 
Hardness,  24  ;  Left-IIanded  Crys- 
tals, 25  ;  Limped,  25  :  Lustre,  24  ; 
Mamillary  Form,  24  ;  Milky,  27  ; 
Phenocrystalline,  25 ;  Polariza- 
tion, 24  ;  Prismatic  Faces,  24  ; 
Pseudomorphous,  33  ;  Radiated, 

26  ;  Kight-Hauded  Crystals,  25  ; 
Kose,  26  ;  Sageiiite,  27  ;  Sapphire, 

27  ;  Siderite,  27.;  Size  of  Crys- 
tals, 24  ;  Smoky,  27  ;  Soluble  in 
Fluohydric  Acid,  25 ;  Specific 
Gravity,  24  :  Stalactitic,  24  ;  Star, 
26  ;  Streak,  24  ;  Swinuning,  36  ; 
Symbol,  25;  Tabular,  33;  Varie- 
ties of,  326 ;  Vitreous  Varieties,  25 

Quartzose  Sandstone,    33 

Quicklime  Lighter  than  Lime,   63 

Radiated  (iuaitz,   26 

Rail  Road  Sleepers,  51 ;  Protection 

of,  210  ;  Secured,  142. 
Rails  of  Ik'achWood,  160  ;  of  Scotch 

Fir,  ir.9, 

Raudanite,   36 

Ransome's  Artificial  Stone,   54 

Ransome's  Experiment,   17 

Raw  Oxide   13S 

Reaction  of  Hydrate  of  Lime,   68 

Reduction  to  Granular  Condition,.  38 
Reef  Building  Coral,  286;  120  Spe- 
cies, 286, 

Reese's  Cement,   78,  105 

Relative   Claims   of   Wood  nnd 

Metal  as  Material  for  Rails   157 

Remarks  of  Dr.  Liebig,  265  ;  of  Dr. 
Lowe,  264  ;  of  T.  Sterry  Hunt,  . .  268 

Report  on  Wooden  Railways,  158 

Resin  Opal,  ,   35 

Reverberatory  Furnace,   41 

Rich  Lime   61.  64 

Richmond,  Va.,  Stratum,   20 

Right-Handed  Crystal  Quartz,  ....  25 

River  Be  his,   19 

River  Sand  from  Mississippi,  37 ; 
from  New  Jersej',  87. 

Robbins  and  Moll's  Patent,   175 

Robbins' Patent,  172;  Pavement,.  205 

Rochetta,   19 

Rock  Crystal,   824 

Rocks,  Arrangement  of,  305  ;  Divi- 
sion in  Ages,  305  ;  Sedimentary, 
304 ;  Sub-Division  of  Geological 
Time,  307  ;  Sub-Division  of  Lyell,  888 

Rocky  Masses  Divided  305 

Roman  Cement,  65,  104;  Where 
Manufactured,  104. 

Roman  Mortar,   96 

Rondout  Hydraulic  Lime,  Analysis 
of,  75. 


Roofing  Cement,   53 

Rose  Quartz,   26 

Rosin,   145 

Rough  Mortar,   128 

Royal  Theatre,  Munich   16 

liumford's  Experiments,  169 

S.agenite  Quartz,  ;   27 

Salt,  140  ;  Dunging,  15  ;  Deposits, 
313;  How  Obtained.  313;  Its 
Uses,  313  :  Glauber,  40,  138. 

Salts  of  Strassford,   812 

Saltpetre  Formation,  119 ;  from 
Mammoth  Cave,  121  ;  Missouri, 
121 ;  Tennessee,  121. 
Sand,  316  ;  Alluvial,  37  ;  Angular 
Grains,  37  ;  Ancient  Law  for,  98  ; 
Calcination  of,  48:  Digested  in 
Chlorohydric  Acid,  38  :  Granitic, 
37;  Green,  105,  817;  Vol- 
canic, 37. 
Sandstone,  315  ;  Argillaceous,  37  ; 
Common,  87;  Flexible,  33, 37;  Imi- 
tation, 57  :  Murly,  37  :  Micaceous, 
37  ;  Quartzose,  33  ;  Silicification 
of,  124  ;  Volcanic,  37, 

Sap,  Aualvsis.of,   164 

Sapi)hire  ^iuartz   27 

Sardonyx,   31 

Sea  Water,  Utilization  of,   312 

Secret  of   the    Venetian  Fiddle 

Makers,   14'J 

Sedimentary  Rocks,   804 

Beeley's  Pavement,  178,  205  ;  Fail- 
ure on  Fifth  Avenue,   205 

Separati<m  of  Sulphur,   42 

SeptJiria,   75 

Sheatliing  Vessels,  Substitute  for, .  15 

Shells,  Silicified,    84 

Shingles,  Protection  against  Fire, 
210  ;  against  Rot,  127  ;  Incombus- 
tible, 127, 

Ship  Timber   15,  61 

Shrinkage  of  Wood,   169 

Siderite  Quartz,   27 

Siemen's  Ajiparatus,  45 ;  Descrip- 
tion, 45  ;  Patent,  45  ;  Pressure 
of  Five  AtmuBpheres,  45. 
Silica,  21,  315;  Acid.  22:  Condensa- 
tion of.  119:  Fusible  in  Oxygen, 
Infusible,  23:  in  Mortar,  93;  In- 
soluble, 22;  Pure,  38:  Soluble  in 
Water  and  Acids.  22;  The  Fee- 
blest Acid,  23;  with  Two  Modifi- 
cations, 22. 
Silica  Painting,  132;  on  Glass,  Me- 
tals, Zinc  or  Porcelain,  132 ;  Semi- 
Transparent  Colors,  132. 

Silica  Jelly,   20 

Silicate  of  Lime,  Conversion  of,  134 

Silicate  Painting,  117 ;  Brush,  117; 

Oak  and  Mai)le  Take  Fire  210  «, .  127 
Silicate,  Alkaline,  94;  Anhydrous, 
39;  Hydrous,  39;  injection  of, 
117;  Natural,  119,  of  Lime,  18; 
Potash,  13 ;  Potash  and  Lime,  15  ; 
Puzzuolanic,  69 ;  Soda,  13, 


366 


INDEX. 


Silicated  Alkali,  Slow  Decomposi- 
tion of,   119 

Silicious  Sinter,  31 ;  Clay,  75, 
Silicification  of  Artificial  Stone,  123; 
by  Atmospheric  Carbonic  Acid, 
123 ;  Lime  Silicate  Forming,  123 ; 
of  Carbonated  Metallic  Salts, 
124;  of  Chalk,  58;  of  Fat  Lime, 
113;  of  Gypsum,  114;  of  Lime- 
stone, 131 ;  of  Mortar,  113 ;  Por- 
ous Limestones,  113;  of  Sand- 
stone, 124;  of  Wood,  140;  Arrest- 
ing Combustion,  140;  Dry  Eot, 
140 ;  Inflamibility,  140. 
Silicifled  Shells,  84;  Wood,  34. 

Siiico  Carbonate  of  Lime,   16 

Silicium,  21;  InHamibility,  22; 
Oxygen,  22, 

Siliciuret  Potassium,   31 

Silex,   21 

Size  of  Quartz  Crystals   24 

Slate,  Cement,  52 ;  Tripoli,  36. 

Slippery  and  Unstable  Footing,   194 

Slow  Decomposition,  153;  of  Sili- 
cated Alkali,  119, 

Smoky  Quartz,   27 

Soap,  a  Substitute  for,  221 

Soda  Ash,  818;  Its  Manufacture, 

314 ;  Purifying  of,  39. 
Soda  Felspar,  39 ;  Nitrate,  40 ;  Sili- 
cate, 13;  Applied  with  Syringe, 
126;   Ai)t  to  Shrink  on  Wood, 
126  ;  for  Painting  on  Walls,  126. 

Soda  Soluble  Glass,   42 

Sodium,  312;  Compounds,  313. 

Solid  Glass,  Vitreous,   44 

Solidifying  Property  of  Cement, . . .  102 

Solid  Surface  of  the  Globe,   21 

Soluble  Glass,  13,  39, 141 ;  a  Substi- 
tute for  Soap,  219 ;  for  Glue,  221 ; 
for  Bookbinders'  Paste,  221  ;  for 
Mucilage,  221;  Fuchs,  13;  Kaul- 
bach's,  44 ;  Manure  for  Grape 
Vines,  219;  Uniform  Application 
of,  128 ;  Used  at  Munich  Theatre,  129 

Soluble  Quartz,   25 

Soluble  Salts,  Extraction  of,   55 

Solution  of  Copperas,  144;  of  Puri- 
fied Mass,  42;  of  Powdered  Flint, 
43;  in  Caustic  Lye,  43;  under 
Pressure,  43, 

SorePs  Cement,   103 

Sparks  of  Locomotives,  149 

Spandau  State  Prison,   16 

Speaker's  Court,   18 

Specific  Gravity  Quartz,   24 

Speculation  on  the  Origin  of  Lime,.  277 

Spiles,   15 

Spirits  Turpentine  Barrels,   210 

Springs  of  Carlsbad  and  Selzer,   253 

Stafford  Pavement   178,  204 

Stafl"ordshire  Coal  contains  A}4  per 

cent.  Phenic  Acid,   174 

Stalactitic  Quartz,    24 

Star  Quartz,   26 

Statement  of  Pliny,   19 


State  Prison  in  Spaudau,   16 

Staves,  Protection  of,   210 

Steam  Eesisting  Cement,   7T,  224 

Stereo-Chromic,  125;  Addition  of 
Oxide  of  Zinc,  125;  Basis  of  Easel 
Painting,  137 ;  by  Trituration, 
125 ;  by  Sulphate  Baryta,  125; 
Both  Agree  with  Silica,  125 ;  Co- 
lors Unite  with  Silica,  126  ;  on 
Stone,  125;  Painting,  44;  Prevent 
Decomposition,  125, 

Stilbite,   39,  122 

Stindc's  Cement,   96 

Stone  and  Wood  Pavement,  Objec- 
tion to,   188 

Stone  Cement,  74  ;  Coating  on,  207 ; 
Disintegration  of,  55 :  Lithograph- 
ic, 137;  Lydian,  32;  Mocha,  31. 

Stove  Cement,   226 

Stowe  Pavement,   203 

S  trass,   340 

Strassfurth  Salts,   312 

Strass  Glass,    13 

Strata,  Argillaceous,   104 

Stratified  PvOcks,  Thickness  of,. . . .  306 

Stratum  hi  Richmond,  Va.,   20 

Streak  Quartz,   24 

Street  Pavement,  177;  Asphalt, 
179;  Belgian,  178;  Concrete,  179; 
Mac  Adam's  System,  180;  Nicol- 
son,  177:  Parisian,  179;  Seely's 
Patent,  178  ;  Stafford,  178. 

Strong  Iron  Cement,   116 

Stucco,   66 

Subsilioates,   39 

Substitute  for  Sheathing  Vessels, 
15;  for  White  Lead,  139;  for 
Zinc  White.  139. 

Sulphate  of  Baryta,  Artificial,  138 

Sulphate  of  Copper,  145;  of  Cadmium, 
126  ;  of  Soda,  40. 

Sulphuric  Acid,   138 

Sweetening  Water,   226 

Swimming  Quartz,   36 

Symbol  Quartz,   25 

System  of  MacAdam  in  1816, 184; 
of  Prosser,  162;  of  Tall,  214; 
Various,  196. 

Table  of  Equivalents,   239 

Tabular  Quartz,   83 

Tanks,  Protection  of,   210 

Tail's  System,   214 

Telegraph  Poles,  51 ;  Protection  of,  210 

Terra  Cotta  Cement   79,  105 

Teredo  N avails,  16;  Feed  upon 
Borings  of  Wood,  147. 

Tertiary,   20 

Test  of  Water  Lime,   101 

Theory  of  Vicat,   68 

Thickness  of  Coral  Formations,  285 ; 

of  Stratified  Rocks,  306. 
Timber,  Drying  of,  170,  Chemical 
Process,  162;  for  Houses,  51 ;  for 
Ships,  15 ;  Protection  of,  210 ;  Kot 
and  Seasoning,  162. 
Toadstones   75 


INDEX. 


357 


Touchstone,   32 

Traffic,  Nature  of,   195 

Trass,   100 

Travertin,   293 

Treatise,  of  Neri,   19 

Triassic  Period,   104 

Tripolite,  36  ;  Variety  of,  37. 

Tripoli  Slate,   36 

Typical  Uistorical  Pavement,   191 

Ulster  Quartz,   34 

Ultramarine,  Blue  and  Green,  126  ; 
Enamel,  133. 

Umber,    138 

Underground,  Preparing,   130 

Uniform  Application   of  Soluble 

Glass,   128 

Unisilicatcs,   39 

Upper  Ground  for  Painting,   137 

Upward  Increase  of  Reef  Ground 

per  Year   282 

Utilization  of  Sea  Water,   812 

Valley  of  Death   253 

Van  llclmont,   19 

Variety  of  Glass,  339:  of  Quartz, 

326:  of  Tripolite,  37. 
Various  Cements,  222 .  Hues  of 
Glass,  342;  Systems,  196. 

Vascular  Tissue  Juice   164 

Vegetable  Albumen,  (^ause  of  De- 
cay,  164 

Venetian  Fiddle  Makers'  Secret,. . .  149 
Vicat's  Hydraulic  Masonry,  103: 
Method,'  102:    Mixture,  103: 
Theory,  68. 

Violitter's  Process,   148 

A'itreous  Solid  (ilass,  44  :  Variety 

of  Quartz,  ".  25 

Vitrifying  Kali.   19 

Volcanic  Dust,  99 :  Pumice,  99 ; 
Sand.  37  :  Sandstone,  37, 

Wall  Damp  Concrete   81 

Walls  of  Bastile,  99 ;  Preserva- 
tion of,  209. 


I  Walnut  Changes  Color,   148 

Water  Glass,  13:  Compound,  16; 

Potash,  18:  Simple,  16. 
Water  Lime,  100 ;  Lime  Test,  101  ; 
in  Wood,  6S  ;   8^veetening,  226  ; 
Tank  Cement,  214. 
Waves  as  Destructive  to  Corals  as 


Winds  to  Forests,   284 

Waves  Destroy  and  Reduce  Coral 

Fr.igmcnts   284 

Westminster  \bbey,   18 

White  Arsenic, ...   40 

:  White  Load,  Substitute  for,   139 

VV  bite  Paint,  Cheap,   126 

White,  Permanent,   188 

White  Stone,   48 

!  Whitewash  and  Silicate.  84 ;  Cheap- 
est. 213. 

I   Window  Glass,   13 

Wismar  Harbor,   20 

Witherite   138 


Wood  and  Stone  Pavements,  Ob- 
jections to,  188:  Beconu  s  Strong- 
er. 149  .  Exposure  to  480°  Steam, 
148:  Non-Inflamible,  51  ;  Opal, 
36:  Painting  I'eels  oflF,  127; 
Shrinkage  of,  169:  Silicification 
of,  34.  140 :  Suitable  for  Musical 
Instruments,  149. 
Wooden  Buildingp,  127:  Exposed 
to  Vapor,  127  :  Change  of  Tem- 
perature. 127. 

Wooden  Pavements.  Merita  of,   1S8 

Wooden  Railways.  Report  on,   158 

Wooden  Roof  Shingles,   149,  176 

Wool  Growers'  Uses,   52 

Yellow  and  White  Pine,  167 

I   Yellow  Ochre   126,  138 

I   Yelh)W  Quartz,   27 

Yellow  Wash,  Cheapest,  213 

Zeolites,   89 

Zinc  Cement,  224 

Zinc  White,  Suitablo  for,   139 


« 


ERRORS, 


WHICH   HAVE   BEEN   OVERLOOKED,   AND    WILL    BE  CORRECTED 
IN  THE  NEXT  EDITION  BY  THE  AUTHOR. 


For 


refractory,  read  reverboratory,  page  13,   4th  line. 

silica^ 

a 

silicic, 

lO,  ISl 

when, 

u 

then. 

^z,  luin        I.  D. 

shist, 

u 

cr>  ni 

Oty      XV  til 

fine. 

^^ 

fire. 

"    35  14th    "  " 

acidity, 

allvali, 

silification, 

silicification, 

"    58,  13th    "  " 

linicular. 

u 

lenticular, 

75,    2d     "  " 

sillification, 

u 

silicification, 

"  113,    6th    "  " 

do. 

u 

do. 

"  113,  16th    "  " 

do. 

do. 

"  114,  11th    "  " 

do. 

u 

do. 

"  131,  10th    "  " 

appled. 

u 

applied. 

"  133,    2d     "  " 

sillification. 

u 

silicification. 

"  140,  at  the  head,  an 

the  whole  chaptei 

colito. 

oolite. 

"  283,  2d  line. 

sihivian. 

Silurian, 

"  300. 

is. 

a 

are, 

"  297. 

ooletic. 

ii 

oolitic. 

"  295. 

group. 

u 

gravity. 

"  289. 

150,000,000, 

read  150,000, 

"  309 

GETTY  RESEARCH  INSTITUTE 


3  3125  01000  9195 


